0001437749-23-023081 | 10-Q | XBRL Viewer

Research, Development, and Computer Software Disclosure [Text Block]

7. Research Grants and Agreements

Sponsored Research Agreement

The Company may sponsor research activities (“SRAs”) performed by ODURF. ODURF is compensated by the Company for its conduct of each study in accordance with the budget and payment terms set forth in the applicable task order. In March 2021, the Company agreed to sponsor a task order in the amount of $0.3 million for research performed during the subsequent 12-month period to be funded through monthly payments to ODURF. In May 2021, the Company agreed to sponsor an additional task order in the amount of $0.3 million for research performed during the subsequent 12-month period. These SRAs are funded through monthly payments to ODURF. Payments will be made upon ODURF certifying, to the Company’s reasonable satisfaction, that ODURF has met its obligations pursuant to the specified task order and statement of work. The principal investigator may transfer funds with the budget as needed without the Company’s approval so long as the obligations of ODURF under the task order and statement of work remain unchanged and unimpaired. During the three-month and six-month periods ended June 30, 2023, the Company did not incur any costs relating to the SRAs. During the three-month and six-month periods ended June 30, 2022, the Company recorded costs relating to the SRAs equal to $0.1 million and $0.2 million, respectively. As of June 30, 2023, the Company does not have any active SRAs with ODURF.

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2022
Rights Offering [Member]
Issuance cost	$ 111	$ 111

Note 12 - Related Party Transactions (Details Textual) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended
	May 31, 2023	Apr. 30, 2023	Sep. 20, 2022	Mar. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Accrued Liabilities, Current					$ 2,844	$ 2,595
Common Stock, Par or Stated Value Per Share (in dollars per share)					$ 0.001	$ 0.001
Loan Agreement [Member]
Debt Instrument, Decrease, Forgiveness		$ 65,000
Interest Payable		$ 200
Robert W. Duggan [Member] \| Private Placement [Member]
Stock Issued During Period, Shares, New Issues (in shares)		10,022,937
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001
Shares Issued, Price Per Share (in dollars per share)		$ 6.51
Letter Agreement [Member] \| Robert W. Duggan [Member]
Directors and Officers Liability Insurance, Period (Year)				1 year
Related Party Transaction, Amounts of Transaction	$ 1,000		$ 65,000
Accrued Liabilities, Current					$ 0

Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Market-based Option Activity (Details) - Market-based Options [Member] - $ / shares	6 Months Ended
	Jun. 30, 2023
Options balances, number of shares (in shares)	0
Options balances, weighted average exercise price (in dollars per share)	$ 0
Options granted, number of shares (in shares)	1,000,000
Options granted, weighted average exercise price (in dollars per share)	$ 6.44
Options exercised, number of shares (in shares)	0
Options exercised, weighted average exercise price (in dollars per share)	$ 0
Options canceled, number of shares (in shares)	0
Options canceled, weighted average exercise price (in dollars per share)	$ 0
Options expired, number of shares (in shares)	0
Options expired, weighted average exercise price (in dollars per share)	$ 0
Options balances, number of shares (in shares)	1,000,000
Options balances, weighted average exercise price (in dollars per share)	$ 6.44
Options balances, weighted average remaining life (Year)	9 years 9 months 29 days
Options exercisable, number of shares (in shares)	0
Options exercisable, weighted average exercise price (in dollars per share)	$ 0

Note 4 - Balance Sheet Components (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Depreciation	$ 100	$ 100	$ 271	$ 347
Finite-Lived Intangible Asset, Useful Life (Year)	12 years		12 years

Note 5 - Goodwill (Details Textual) $ in Thousands	6 Months Ended	12 Months Ended
Note 5 - Goodwill (Details Textual) $ in Thousands	Jun. 30, 2023 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2022 USD ($)
Goodwill, Ending Balance	$ 2,791		$ 2,791
Goodwill, Impairment Loss	$ 0
Series of Individually Immaterial Business Acquisitions [Member]
Number of Businesses Acquired		3
Business Combination, Consideration Transferred, Total		$ 5,500
Goodwill, Ending Balance		$ 2,800

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References + Details

Note 9 - Controlled Launch

6 Months Ended

Jun. 30, 2023

Controlled Launch [Text Block]

9. Controlled Launch

In February 2021, the Company received 510(k) clearance from the FDA for its proprietary CellFX System for dermatologic procedures requiring ablation and resurfacing of the skin. In January 2021, the Company received CE marking approval for the CellFX System, which allows for marketing of the system in the EU for treatment of general dermatologic conditions, including SH, SK, and cutaneous non-genital warts. Additionally, in June 2021 the Company received Health Canada approval for the CellFX System, which allows for marketing of the system in Canada for use in dermatological procedures requiring ablation and resurfacing of the skin for the reduction, removal, and/or clearance of cellular-based benign lesions. In February 2021, the Company commenced a controlled launch of the CellFX System in the United States and European Union via its CellFX Expectations Excelled Program (the “Controlled Launch”). Subsequent to receiving Health Canada approval in June 2021, the Company also commenced its Controlled Launch in Canada.

As part of the Controlled Launch, the Company selected 70 physicians and their practices to be the first physician consultants to launch the CellFX System and the associated CellFX commercial procedures into their respective markets and geographies. In the Controlled Launch program, the Company provided and set up a CellFX System at each physician site and provided the physician with the necessary related products and components, free of charge, to complete the requirements of the Controlled Launch program. Each CellFX System and any unused component products remained the property of the Company throughout the Controlled Launch program. Under the Controlled Launch program, each physician was to identify and recruit up to 40 or 50 patients, depending on the contract, for participation in the Controlled Launch, performing a CellFX procedure on each of the appropriately selected patients. The physician and their patients completed evaluation surveys about their experiences with the CellFX System and provided other information helpful to the Company. Upon completion of the procedures and the survey feedback, the physician earned credits to be used towards the future purchase of the CellFX System or, in some jurisdictions, fair payment for their time and effort completing the paperwork required under the Controlled Launch program. Credits earned and, if applicable, any other payments earned were limited to a maximum amount dependent on the number of surveys received by the Company. Upon completion of the Controlled Launch program requirements, each physician could choose to enter into a purchase agreement with the Company, under which the physician could use the credits earned (or other payments earned, as applicable) towards the purchase of the already-delivered CellFX System, or the physician could return the CellFX System to the Company.

As patient procedures and surveys were completed under the Controlled Launch program, the Company accrued the value of the credits earned, which were recorded in accrued expenses, with a corresponding charge to sales and marketing expense. The Company did not record any sales and marketing expense in relation to the Controlled Launch program for the three-month or six-month periods ended June 30, 2023, and it recorded an expense of $0.1 million and $0.6 million for the three-month and six-month periods ended June 30, 2022, respectively.

In September 2022, the Company concluded the Controlled Launch program and notified all remaining program participants. In accordance with the Controlled Launch program, physicians having completed the program requirements could elect to purchase their already delivered CellFX System, applying credits earned, or return the CellFX System to the Company. The Company concluded these efforts in the fourth quarter of 2022 and has discontinued sales of the CellFX System, although the Company continues to offer its disposable treatment tips to dermatologists who have chosen to retain their existing CellFX consoles.

During the six months ended June 30, 2023, the Company did not recognize any revenue in relation to the Controlled Launch program. During the three-month and six-month periods ended June 30, 2022, certain consultants completed the Controlled Launch program and entered into purchase agreements with the Company, whereby they used their credits or other earned payments towards the purchase of a CellFX System. Accordingly, approximately $0.1 million and $0.4 million of the accrued liability related to the Controlled Launch program was relieved and recognized as revenue on a non-cash basis as a result of these purchases during the three-month and six-month periods ended June 30, 2022, respectively. See Note 10 for additional detail of revenue transactions.

Note 2 - Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2023

Schedule of Product Warranty Liability [Table Text Block]

	*Three Months Ended June 30,*					*Six Months Ended June 30,*
	*2023*			*2022*		*2023*			*2022*
Beginning balance	$	50		$	97	$	50		$	80
Add: Accruals for warranties issued during the period		—			25		—			42
Less: Adjustment for inventory at cost		(50	)		—		(50	)		—
Ending balance	$	—		$	122	$	—		$	122

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	*Six Months Ended June 30,*
	*2023*		*2022*
Common stock warrants		—		7,310,917
Common stock options		6,888,015		5,608,140
Total		6,888,015		12,919,057

Note 4 - Balance Sheet Components

6 Months Ended

Jun. 30, 2023

Supplemental Balance Sheet Disclosures [Text Block]

4. Balance Sheet Components

Property and Equipment, Net

Property and equipment, net consisted of the following (in thousands):

	*June 30,*			*December 31,*
	*2023*			*2022*
Leasehold improvements	$	2,519		$	2,519
Laboratory equipment		1,188			1,118
Furniture, fixtures and equipment		966			966
Software		296			289
Construction in progress		10			22
		4,979			4,914
Less: Accumulated depreciation and amortization		(3,224	)		(2,953	)
	$	1,755		$	1,961

Depreciation expense was $0.1 million for the three-month periods ended June 30, 2023 and 2022, and $0.3 million for the six-month periods ended June 30, 2023 and 2022, respectively.

Intangible Assets, Net

Intangible assets primarily consist of acquired licenses to utilize certain patents, know-how and technology relating to the Company’s NPS technology for biomedical applications acquired from Old Dominion University Research Foundation (“ODURF”), Eastern Virginia Medical School, and the University of Southern California. In addition, the Company entered into a Sponsored Research Agreement with Old Dominion University’s Frank Reidy Research Center for Bioelectrics, which includes certain intellectual property rights arising from the research. The Company is amortizing the intangible assets over an estimated useful life of 12 years.

Intangible assets, net consisted of the following (in thousands):

	*June 30,*			*December 31,*
	*2023*			*2022*
Acquired patents and licenses	$	7,985		$	7,985
Less: Accumulated amortization		(5,767	)		(5,434	)
	$	2,218		$	2,551

A schedule of the amortization of intangible assets for the remainder of 2023 and the succeeding three fiscal years is as follows (in thousands):

Years ending December 31:
2023 (remaining 6 months)	$	333
2024		665
2025		665
2026		555
	$	2,218

Accrued Expenses

Accrued expenses consisted of the following (in thousands):

	*June 30,*		*December 31,*
	*2023*		*2022*
Compensation expense	$	2,123	$	1,377
Director and officer liability insurance (Note 12)		—		571
Clinical trial fees and costs		49		64
Professional fees		503		318
Warranty		—		50
Other		169		215
	$	2,844	$	2,595

Note 8 - Commitments and Contingencies - Information Related to Right-of-use Assets and Lease Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Right-of-use assets	$ 7,670		$ 8,062
Current operating lease liabilities	975		896
Non-current operating lease liabilities	8,644		9,144
Total lease liabilities	9,619		$ 10,040
Cash paid for operating lease liabilities	907	$ 894
2023 (remaining 6 months)	937
2024	1,910
2025	1,977
2026	2,046
2027	2,117
Thereafter	4,075
Total lease payments	13,062
Less imputed interest	$ (3,443)
Weighted-average remaining lease term (Year)	6 years 4 months 2 days
Weighted-average discount rate	10.00%

Note 6 - Stockholders' Equity and Stock-based Compensation - Stock-based Compensation Expense by Type (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Total stock-based compensation expense	$ 1,143	$ 1,143	$ 1,713	$ 2,039	$ 3,720
Time-based Options [Member]
Total stock-based compensation expense	876		1,445	1,554	3,252
Performance-based and Market-based Options [Member]
Total stock-based compensation expense	245		132	362	215
Employee Stock Purchase Plan Award [Member]
Total stock-based compensation expense	$ 22		$ 136	$ 123	$ 253

Note 3 - Fair Value of Financial Instruments

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Text Block]

3. Fair Value of Financial Instruments

The authoritative guidance with respect to fair value established a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three levels, and requires that assets and liabilities carried at fair value be classified and disclosed in one of three categories, as presented below.

Level 1 - Observable inputs such as quoted prices in active markets for an identical asset or liability that the Company has the ability to access as of the measurement date. Financial assets and liabilities utilizing Level 1 inputs include money market funds.

Level 2 - Inputs, other than quoted prices included within Level 1, which are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Financial assets and liabilities utilizing Level 2 inputs include commercial paper, corporate bonds, U.S. Treasury Securities, and asset-backed securities.

Level 3 - Unobservable inputs for which there is little or no market data for the asset or liability which requires the reporting entity to develop its own assumptions. The Company did not classify any of its investments within Level 3 of the fair value hierarchy.

The following table sets forth the fair value of the Company’s financial assets measured on a recurring basis as of June 30, 2023 and December 31, 2022, respectively (in thousands):

		*June 30, 2023*
Assets	*Classification*	*Level 1*		*Level 2*		*Level 3*		*Total*
Money market funds	Cash and cash equivalents	$	56,388	$	—	$	—	$	56,388
Total assets measured at fair value		$	56,388	$	—	$	—	$	56,388

		December 31, 2022
Assets	Classification	Level 1		Level 2		Level 3		Total
Money market funds	Cash and cash equivalents	$	57,973	$	—	$	—	$	57,973
Total assets measured at fair value		$	57,973	$	—	$	—	$	57,973

The Company did not have any financial liabilities measured on a recurring basis as of June 30, 2023 or December 31, 2022.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Note 11 - Segment Reporting (Details Textual)	6 Months Ended
Note 11 - Segment Reporting (Details Textual)	Jun. 30, 2023
Number of Reportable Segments	1

Note 2 - Summary of Significant Accounting Policies - Antidilutive Securities (Details) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Antidilutive securities (in shares)	6,888,015	12,919,057
Warrant [Member]
Antidilutive securities (in shares)	0	7,310,917
Share-Based Payment Arrangement, Option [Member]
Antidilutive securities (in shares)	6,888,015	5,608,140

Note 1 - Description of the Business

6 Months Ended

Jun. 30, 2023

Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]

1. Description of the Business

Pulse Biosciences, Inc. is a novel bioelectric medicine company committed to health innovation using its patented Nano-pulse Stimulation (“NPS”) technology, a revolutionary energy modality that delivers nanosecond-duration pulses of electrical energy, each less than a millionth of a second long, to non-thermally clear targeted cells while sparing adjacent noncellular tissue. NPS technology, also referred to as a Nanosecond Pulsed Field Ablation (“nsPFA”) technology when used to ablate cellular tissue, can be used to treat a variety of medical conditions for which an optimal solution remains unfulfilled. The Company developed its proprietary CellFX System, a novel nsPFA delivery platform, and commercialized the initial application of its nsPFA technology to treat benign lesions of the skin. In parallel, the Company has designed a variety of applicators to explore the potential use of the CellFX platform to treat disorders in other medical specialties, such as cardiology, gastroenterology, gynecology, and ear, nose and throat. These applicators include devices for open surgical procedures, endoscopic or minimally invasive procedures, and endoluminal catheters, and each has been used in preclinical studies. Based on our preclinical experience and the potential to significantly improve outcomes for patients in a large and growing market, the Company decided in 2022 to focus its efforts on the use of nsPFA applicators and the CellFX platform in the treatment of atrial fibrillation (“AF”).

The Company was incorporated in Nevada on May 19, 2014. On June 18, 2018, the Company reincorporated from the State of Nevada to the State of Delaware. The Company is located in Hayward, California. The Company maintains a website at www.pulsebiosciences.com where general information about the Company is available.

The Company’s activities are subject to significant risks and uncertainties, including the need for additional capital. The Company does not currently have any material cash flows from operations. It has had minimal revenue and currently generates no revenue and will need to raise additional capital to finance its operations. However, there can be no assurances that the Company will be able to obtain additional financing on acceptable terms and in the amounts necessary to fully fund its operating requirements.

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Private Placement [Member] Common Stock [Member]	Private Placement [Member] Additional Paid-in Capital [Member]	Private Placement [Member] AOCI Attributable to Parent [Member]	Private Placement [Member] Retained Earnings [Member]	Private Placement [Member]	Rights Offering [Member] Common Stock [Member]	Rights Offering [Member] Additional Paid-in Capital [Member]	Rights Offering [Member] AOCI Attributable to Parent [Member]	Rights Offering [Member] Retained Earnings [Member]	Rights Offering [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2021											29,716
Balance at Dec. 31, 2021											$ 29	$ 271,861	$ 0	$ (236,200)	$ 35,690
Issuance of common stock pursuant to warrant exercise (in shares)											7
Issuance of common stock pursuant to warrant exercise											$ 1	12			13
Stock-based compensation expense											0	3,720	0	0	3,720
Net loss											$ 0		0	(31,269)	(31,269)
Issuance of shares under employee stock purchase plan (in shares)											86
Issuance of shares under employee stock purchase plan											$ 0	372			372
Issuance of shares in Rights Offering, net of issuance costs of $111 (in shares)						7,317
Issuance of shares in Rights Offering, net of issuance costs of $111						$ 7	$ 14,882	$ 0	$ 0	$ 14,889
Balance (in shares) at Jun. 30, 2022											37,126
Balance at Jun. 30, 2022											$ 37	290,847	0	(267,469)	23,415
Balance (in shares) at Mar. 31, 2022											29,802
Balance at Mar. 31, 2022											$ 29	274,240	0	(253,473)	20,796
Issuance of common stock pursuant to warrant exercise (in shares)											7
Issuance of common stock pursuant to warrant exercise											$ 1	12			13
Stock-based compensation expense											0	1,713	0	0	1,713
Net loss											$ 0		0	(13,996)	(13,996)
Issuance of shares in Rights Offering, net of issuance costs of $111 (in shares)						7,317
Issuance of shares in Rights Offering, net of issuance costs of $111						$ 7	$ 14,882	$ 0	$ 0	$ 14,889
Balance (in shares) at Jun. 30, 2022											37,126
Balance at Jun. 30, 2022											$ 37	290,847	0	(267,469)	23,415
Balance (in shares) at Dec. 31, 2022											37,235
Balance at Dec. 31, 2022											$ 37	292,420	0	(294,705)	(2,248)
Issuance of common stock as part of debt extinguishment, net of issuance costs of $6 (in shares)	10,023
Issuance of common stock as part of debt extinguishment, net of issuance costs of $6	$ 10	$ 65,233	$ 0	$ 0	$ 65,243
Issuance of common stock pursuant to warrant exercise (in shares)											7,238
Issuance of common stock pursuant to warrant exercise											$ 7	14,820	0	0	14,827
Issuance of common stock upon exercise of stock options (in shares)											13
Issuance of common stock upon exercise of stock options											$ 0	58	0	0	58
Stock-based compensation expense											0	2,039	0	0	2,039
Net loss											$ 0	0	0	(19,711)	(19,711)
Issuance of shares under employee stock purchase plan (in shares)											262
Issuance of shares under employee stock purchase plan											$ 1	291	0	0	292
Balance (in shares) at Jun. 30, 2023											54,771
Balance at Jun. 30, 2023											$ 55	374,861	0	(314,416)	60,500
Balance (in shares) at Mar. 31, 2023											37,593
Balance at Mar. 31, 2023											$ 38	293,801	0	(304,506)	(10,667)
Issuance of common stock as part of debt extinguishment, net of issuance costs of $6 (in shares)	10,023
Issuance of common stock as part of debt extinguishment, net of issuance costs of $6	$ 10	$ 65,236	$ 0	$ 0	$ 65,246
Issuance of common stock pursuant to warrant exercise (in shares)											7,142
Issuance of common stock pursuant to warrant exercise											$ 7	14,623	0	0	14,630
Issuance of common stock upon exercise of stock options (in shares)											13
Issuance of common stock upon exercise of stock options											$ 0	58	0	0	58
Stock-based compensation expense											0	1,143	0	0	1,143
Net loss											$ 0	0	0	(9,910)	(9,910)
Balance (in shares) at Jun. 30, 2023											54,771
Balance at Jun. 30, 2023											$ 55	$ 374,861	$ 0	$ (314,416)	$ 60,500

Note 10 - Revenue (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue from Contract with Customer, Excluding Assessed Tax	$ 0	$ 265	$ 0	$ 709
Redemption of Non Cash Credits [Member]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 100	$ 0	$ 400

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Note 11 - Segment Reporting

6 Months Ended

Jun. 30, 2023

Segment Reporting Disclosure [Text Block]

11. Segment Reporting

The Company operates and manages the business as one reportable and operating segment. The Company’s Chief Executive Officer acts as the chief operating decision maker (“CODM”) of the Company. The CODM reviews the results of the Company on a consolidated basis, however in making certain operating decisions and assessing performance, the CODM will additionally review the disaggregated revenue results by product and geography. All of the Company’s long-lived assets are based in the United States.

Revenue by product consisted of the following (in thousands):

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
Systems	$	—	$	209	$	—	$	576
Cycle units		—		56		—		133
Total consolidated revenue	$	—	$	265	$	—	$	709

Revenue by geography consisted of the following (in thousands):

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
North America	$	—	$	214	$	—	$	526
Rest of World		—		51		—		183
Total consolidated revenue	$	—	$	265	$	—	$	709

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Note 11 - Segment Reporting - Revenue by Geography (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Total revenues	$ 0	$ 265	$ 0	$ 709
North America [Member]
Total revenues	0	214	0	526
Rest of World [Member]
Total revenues	$ 0	$ 51	$ 0	$ 183

Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Time-based Option Activity (Details) - Time-based Options [Member]	6 Months Ended	12 Months Ended
	Jun. 30, 2023 $ / shares shares	Dec. 31, 2022 $ / shares shares
Options balances, number of shares (in shares) \| shares	4,730,394
Options balances, weighted average exercise price (in dollars per share) \| $ / shares	$ 12.95
Options balances, weighted average remaining life (Year)	6 years 5 months 23 days	6 years 1 month 28 days
Options granted, number of shares (in shares) \| shares	442,386
Options granted, weighted average exercise price (in dollars per share) \| $ / shares	$ 5.93
Options exercised, number of shares (in shares) \| shares	(12,900)
Options exercised, weighted average exercise price (in dollars per share) \| $ / shares	$ 4.55
Options canceled, number of shares (in shares) \| shares	(127,894)
Options canceled, weighted average exercise price (in dollars per share) \| $ / shares	$ 7.92
Options expired, number of shares (in shares) \| shares	(348,601)
Options expired, weighted average exercise price (in dollars per share) \| $ / shares	$ 13.05
Options balances, number of shares (in shares) \| shares	4,683,385	4,730,394
Options balances, weighted average exercise price (in dollars per share) \| $ / shares	$ 12.44	$ 12.95
Options exercisable, number of shares (in shares) \| shares	3,372,083
Options exercisable, weighted average exercise price (in dollars per share) \| $ / shares	$ 14.47
Options exercisable, weighted average remaining life (Year)	5 years 6 months 7 days

Note 3 - Fair Value of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2023

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

		*June 30, 2023*
Assets	*Classification*	*Level 1*		*Level 2*		*Level 3*		*Total*
Money market funds	Cash and cash equivalents	$	56,388	$	—	$	—	$	56,388
Total assets measured at fair value		$	56,388	$	—	$	—	$	56,388

		December 31, 2022
Assets	Classification	Level 1		Level 2		Level 3		Total
Money market funds	Cash and cash equivalents	$	57,973	$	—	$	—	$	57,973
Total assets measured at fair value		$	57,973	$	—	$	—	$	57,973

Note 5 - Goodwill

6 Months Ended

Jun. 30, 2023

Goodwill Disclosure [Text Block]

5. Goodwill

In 2014, the Company acquired three companies (the “Acquisitions”) for aggregate consideration of $5.5 million. In accordance with ASC Topic 805, Business Combinations, the Company recorded goodwill of $2.8 million in connection with the Acquisitions as the consideration paid exceeded the fair value of the net tangible assets and the intangible assets acquired.

In accordance with ASC Topic 350, Intangibles-Goodwill and Other (as amended by Accounting Standards Update 2017-04), the Company reviews goodwill for impairment at least annually or whenever any events or circumstances indicate that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. The Company performed an updated goodwill impairment analysis as of June 30, 2023, and it was determined that no impairment of goodwill existed.

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenues:
Total revenues	$ 0	$ 265	$ 0	$ 709
Cost and expenses:
Cost of revenues	0	1,344	0	2,253
Research and development	6,697	5,458	12,526	12,227
Sales and marketing	0	3,690	0	9,231
General and administrative	3,530	3,787	7,263	8,285
Total cost and expenses	10,227	14,279	19,789	31,996
Loss from operations	(10,227)	(14,014)	(19,789)	(31,287)
Other income:
Interest income, net	317	18	78	18
Total other income	317	18	78	18
Loss from operations, before income taxes	(9,910)	(13,996)	(19,711)	(31,269)
Income tax benefit	0	0	0	0
Net loss	(9,910)	(13,996)	(19,711)	(31,269)
Other comprehensive gain (loss):
Unrealized gain (loss) on available-for-sale securities	0	0	0	0
Comprehensive loss	$ (9,910)	$ (13,996)	$ (19,711)	$ (31,269)
Net loss per share:
Basic and diluted net loss per share (in dollars per share)	$ (0.22)	$ (0.44)	$ (0.48)	$ (1.02)
Weighted average shares used to compute net loss per common share — basic and diluted (in shares)	44,512	31,492	40,970	30,623
Product [Member]
Revenues:
Total revenues	$ 0	$ 265	$ 0	$ 709

Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Performance Option Activity (Details) - Performance Options [Member]	6 Months Ended	12 Months Ended
	Jun. 30, 2023 $ / shares shares	Dec. 31, 2022 $ / shares shares
Options balances, number of shares (in shares) \| shares	520,302
Options balances, weighted average exercise price (in dollars per share) \| $ / shares	$ 10.08
Options balances, weighted average remaining life (Year)	8 years 11 months 4 days	7 years 7 days
Options granted, number of shares (in shares) \| shares	800,000
Options granted, weighted average exercise price (in dollars per share) \| $ / shares	$ 3.03
Options exercised, number of shares (in shares) \| shares	0
Options exercised, weighted average exercise price (in dollars per share) \| $ / shares	$ 0
Options canceled, number of shares (in shares) \| shares	(37,500)
Options canceled, weighted average exercise price (in dollars per share) \| $ / shares	$ 2.05
Options expired, number of shares (in shares) \| shares	(78,172)
Options expired, weighted average exercise price (in dollars per share) \| $ / shares	$ 12.84
Options balances, number of shares (in shares) \| shares	1,204,630	520,302
Options balances, weighted average exercise price (in dollars per share) \| $ / shares	$ 5.47	$ 10.08
Options exercisable, number of shares (in shares) \| shares	217,564
Options exercisable, weighted average exercise price (in dollars per share) \| $ / shares	$ 10.55
Options exercisable, weighted average remaining life (Year)	6 years 5 months 19 days

Note 4 - Balance Sheet Components (Tables)

6 Months Ended

Jun. 30, 2023

Property, Plant and Equipment [Table Text Block]

	*June 30,*			*December 31,*
	*2023*			*2022*
Leasehold improvements	$	2,519		$	2,519
Laboratory equipment		1,188			1,118
Furniture, fixtures and equipment		966			966
Software		296			289
Construction in progress		10			22
		4,979			4,914
Less: Accumulated depreciation and amortization		(3,224	)		(2,953	)
	$	1,755		$	1,961

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	*June 30,*			*December 31,*
	*2023*			*2022*
Acquired patents and licenses	$	7,985		$	7,985
Less: Accumulated amortization		(5,767	)		(5,434	)
	$	2,218		$	2,551

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

Years ending December 31:
2023 (remaining 6 months)	$	333
2024		665
2025		665
2026		555
	$	2,218

Schedule of Accrued Liabilities [Table Text Block]

	*June 30,*		*December 31,*
	*2023*		*2022*
Compensation expense	$	2,123	$	1,377
Director and officer liability insurance (Note 12)		—		571
Clinical trial fees and costs		49		64
Professional fees		503		318
Warranty		—		50
Other		169		215
	$	2,844	$	2,595

Note 7 - Research Grants and Agreements (Details Textual) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	May 31, 2021	Mar. 31, 2021	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Research and Development Expense			$ 6,697	$ 5,458	$ 12,526	$ 12,227
Old Dominion University Research Foundation [Member] \| Sponsored Research Agreement SRA [Member]
Research and Development Expense			$ 0	$ 100	$ 0	$ 200
Old Dominion University Research Foundation [Member] \| Sponsored Research Agreement SRA [Member] \| Research and Development Arrangement [Member]
Long-Term Purchase Commitment, Amount	$ 300	$ 300

Note 6 - Stockholders' Equity and Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended		3 Months Ended	6 Months Ended			12 Months Ended
	Apr. 30, 2023	Jan. 01, 2023	Jun. 09, 2022	May 31, 2021	Nov. 30, 2017	Jun. 30, 2023	Jun. 30, 2023	Jun. 15, 2023	Jun. 30, 2022	Dec. 31, 2017	Dec. 31, 2022	Feb. 04, 2021
Common Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.001	$ 0.001				$ 0.001
Proceeds from Issuance of Common Stock							$ 0		$ 14,963
Proceeds from Warrant Exercises							14,835		$ 0
Time-based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value							$ 2,000
Time-based Options [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage							25.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)							1 year
Performance Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value							$ 1,900
Market-based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value							$ 4,800
The 2017 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)										10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)										1,500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)		1,200,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Number of Shares (in shares)										1,200,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Percent										4.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)						1,740,008	1,740,008
The 2017 Inducement Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)					10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)					1,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)				1,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)						1,244,626	1,244,626
The 2017 Inducement Equity Incentive Plan [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage					25.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)					1 year
The 2017 Inducement Equity Incentive Plan [Member] \| Share-Based Payment Arrangement, Option [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)					10 years
The 2017 Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)										250,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Number of Shares (in shares)										450,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Percent										1.50%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)						198,529	198,529
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)						0	262,470
Rights Offering Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)			1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 2.05			$ 2.05	$ 2.05
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						7,317,072	7,317,072
Class of Warrants or Rights, Redemption Price Per Share (in dollars per share)						$ 0.01	$ 0.01
Class of Warrant or Right, Period of Written Notice for Exercise (Day)							30 days
Class of Warrant or Right, Percentage Required for Redemption						200.00%	200.00%
Class of Warrant or Right, Exercise, Consecutive Trading Days (Day)							20 days
Class of Warrant or Right, Exercised During Period (in shares)							66,175	7,250,897
Proceeds from Warrant Exercises								$ 14,900
Class of Warrant or Right, Outstanding (in shares)						0	0
Loan Agreement [Member]
Debt Instrument, Decrease, Forgiveness	$ 65,000
Private Placement [Member] \| Robert W. Duggan [Member]
Stock Issued During Period, Shares, New Issues (in shares)	10,022,937
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001
Shares Issued, Price Per Share (in dollars per share)	$ 6.51
Rights Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)			7,317,072
Common Stock, Par or Stated Value Per Share (in dollars per share)			$ 0.001
Shares Issued, Price Per Share (in dollars per share)			$ 2.05
Equity Offering, Units, Sale of Units (in shares)			7,317,072
Number of Shares Per Unit Issued (in shares)			1
Number of Warrants Per Unit (in shares)			1
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			7,317,072
Proceeds from Issuance of Common Stock			$ 15,000
Class of Warrants or Rights, Redemption Price Per Share (in dollars per share)			$ 0.01
Rights Offering [Member] \| Board of Directors Chairman [Member]
Investment Owned, Percent of Net Assets			56.00%
ATM Offering [Member]
Equity Offering, Maximum Offering Amount												$ 60,000

Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Stock Option Activity (Details) - The 2015 Plan, 2017 Plan and Inducement Plan [Member]	6 Months Ended	12 Months Ended
	Jun. 30, 2023 $ / shares shares	Dec. 31, 2022 $ / shares shares
Options balances, number of shares (in shares) \| shares	5,250,696
Options balances, weighted average exercise price (in dollars per share) \| $ / shares	$ 12.67
Options balances, weighted average remaining life (Year)	7 years 4 months 24 days	6 years 2 months 26 days
Options granted, number of shares (in shares) \| shares	2,242,386
Options granted, weighted average exercise price (in dollars per share) \| $ / shares	$ 5.12
Options exercised, number of shares (in shares) \| shares	(12,900)
Options exercised, weighted average exercise price (in dollars per share) \| $ / shares	$ 4.55
Options canceled, number of shares (in shares) \| shares	(165,394)
Options canceled, weighted average exercise price (in dollars per share) \| $ / shares	$ 6.59
Options expired, number of shares (in shares) \| shares	(426,773)
Options expired, weighted average exercise price (in dollars per share) \| $ / shares	$ 13.01
Options balances, number of shares (in shares) \| shares	6,888,015	5,250,696
Options balances, weighted average exercise price (in dollars per share) \| $ / shares	$ 10.35	$ 12.67
Options exercisable, number of shares (in shares) \| shares	3,589,647
Options exercisable, weighted average exercise price (in dollars per share) \| $ / shares	$ 14.23
Options exercisable, weighted average remaining life (Year)	5 years 6 months 29 days

Note 3 - Fair Value of Financial Instruments (Details Textual) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Recurring [Member]
Liabilities, Fair Value Disclosure	$ 0	$ 0

Note 11 - Segment Reporting (Tables)

6 Months Ended

Jun. 30, 2023

Disaggregation of Revenue [Table Text Block]

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
Systems	$	—	$	209	$	—	$	576
Cycle units		—		56		—		133
Total consolidated revenue	$	—	$	265	$	—	$	709

Revenue from External Customers by Geographic Areas [Table Text Block]

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
North America	$	—	$	214	$	—	$	526
Rest of World		—		51		—		183
Total consolidated revenue	$	—	$	265	$	—	$	709

Note 4 - Balance Sheet Components - Intangible Assets, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Less: Accumulated amortization	$ (5,767)	$ (5,434)
Finite-Lived Intangible Assets, Net	2,218	2,551
Acquired Patents and Licenses [Member]
Acquired patents and licenses	$ 7,985	$ 7,985

Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 58,747	$ 61,139
Prepaid expenses and other current assets	1,211	1,008
Total current assets	59,958	62,147
Property and equipment, net	1,755	1,961
Intangible assets, net	2,218	2,551
Goodwill	2,791	2,791
Right-of-use assets	7,670	8,062
Other assets	365	365
Total assets	74,757	77,877
Current liabilities:
Accounts payable	1,794	1,573
Accrued expenses	2,844	2,595
Lease liability, current	975	896
Related party note payable, current	0	917
Total current liabilities	5,613	5,981
Lease liability, less current portion	8,644	9,144
Related party note payable, less current	0	65,000
Total liabilities	14,257	80,125
Commitments and contingencies (Note 13)
Stockholders’ equity:
Preferred stock, $0.001 par value; authorized – 50,000 shares; no shares issued and outstanding	0	0
Common stock, $0.001 par value; authorized – 500,000 shares; issued and outstanding – 54,771 shares and 37,235 shares at June 30, 2023 and December 31, 2022, respectively	55	37
Additional paid-in capital	374,861	292,420
Accumulated other comprehensive income (loss)	0	0
Accumulated deficit	(314,416)	(294,705)
Total stockholders’ equity (deficit)	60,500	(2,248)
Total liabilities and stockholders’ equity	$ 74,757	$ 77,877

Note 6 - Stockholders' Equity and Stock-based Compensation

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Text Block]

6. Stockholders’ Equity and Stock-Based Compensation

Private Placement Securities Purchase Agreement

On April 30, 2023, the Company entered into a Securities Purchase Agreement with Robert W. Duggan, the Company’s majority stockholder and Executive Chairman, pursuant to which the Company agreed to issue and sell to Mr. Duggan 10,022,937 shares of the Company’s common stock, par value $0.001 per share, in a Private Placement, at a price per share of $6.51. The parties completed the Private Placement on May 9, 2023, after satisfying all pre-closing conditions, and the Company issued the full number of shares to Mr. Duggan. The shares were paid for through the cancellation of the principal sum of $65.0 million borrowed by the Company pursuant to the 2022 Loan Agreement (See Note 8), together with all accrued and unpaid interest outstanding owed at the time of closing.

Rights Offering

On June 9, 2022, the Company completed a rights offering (the “2022 Rights Offering") resulting in the sale of 7,317,072 units (the “Units”), at a price of $2.05 per Unit, with each Unit consisting of one share of the Company’s common stock, par value $0.001 per share, and one warrant (the “2022 Rights Offering Warrants”) to purchase one share of common stock at a price of $2.05 per share. The common stock and warrants comprising the Units separated upon the closing of the 2022 Rights Offering and were issued individually. 7,317,072 shares of common stock and warrants to acquire up to an additional 7,317,072 shares of common stock were issued in the 2022 Rights Offering. The Company received aggregate gross proceeds from the 2022 Rights Offering of $15 million. In May 2023, the Company delivered an irrevocable notice of redemption to warrant holders and, on June 16, 2023, it redeemed the last of the outstanding 2022 Rights Offering Warrants at a price of $0.01 per warrant share. See the Common Stock Warrants section below for further details. Robert W. Duggan, the Company’s majority stockholder and Executive Chairman, purchased approximately 56% of the shares offered through the 2022 Rights Offering.

At-the-Market Equity Offering

On February 4, 2021, the Company entered into a sales agreement (the “Sales Agreement”) with Stifel, Nicolaus & Company, Inc. (“Stifel”) as sales agent, pursuant to which the Company may offer and sell, from time to time, through Stifel, up to $60.0 million in shares of common stock, by any method permitted by law deemed to be an “at-the-market” offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended. The Company has no obligation to make any sales of its common stock pursuant to such Sales Agreement. The Company did not issue or sell any shares of common stock under the Sales Agreement during the six months ended June 30, 2023 and 2022, respectively.

Common Stock Warrants

In connection with the 2022 Rights Offering, the Company issued 2022 Rights Offering Warrants to purchase a total of 7,317,072 shares of its common stock at an exercise price of $2.05. The 2022 Rights Offering Warrants were subject to redemption by the Company for $0.01 per underlying share of common stock, on not less than 30 days written notice, if the volume weighted average price of the Company’s common stock equals or exceeds 200% of the exercise price for the warrants, subject to adjustment, per share, for 20 consecutive trading days, provided that the Company may not redeem the warrants prior to the date that is three months after the issuance date. On May 10, 2023, the Company issued a press release announcing that on May 9, 2023 the terms for warrant redemption had been met. Pursuant to the redemption, the Company redeemed 66,175 warrants on the redemption date, June 16, 2023. Prior to the redemption date, warrants to purchase 7,250,897 shares were exercised, generating approximately $14.9 million of total gross proceeds to the Company. As of June 30, 2023, there were no 2022 Rights Offering Warrants outstanding.

Equity Plans

2017 Equity Incentive Plan and 2017 Inducement Equity Incentive Plan

The Board of Directors of the Company (the “Board”) previously adopted, and the Company’s stockholders approved, the Company’s 2017 Equity Incentive Plan (the “2017 Plan”).

The 2017 Plan has a 10-year term, and provides for the grant of stock options, stock appreciation rights, restricted stock, restricted stock units, performance units, and performance shares to employees, directors and consultants of the Company and any parent or subsidiary of the Company, as the Compensation Committee of the Board may determine. Subject to an annual evergreen increase and adjustment in the case of certain capitalization events, the Company initially reserved 1,500,000 shares of the Company’s common stock for issuance pursuant to awards under the 2017 Plan. In addition, shares remaining available under the Company’s 2015 Equity Incentive Plan, as amended (the “2015 Plan”), and shares reserved but not issued pursuant to outstanding equity awards that expire or terminate without being exercised or that are forfeited or repurchased by the Company will be added to the shares of common stock available for issuance under the 2017 Plan. The 2017 Plan is administered by the Board’s Compensation Committee. Effective January 1, 2023, the number of shares of common stock available under the 2017 Plan increased automatically by 1,200,000 shares pursuant to the evergreen provision of the 2017 Plan, which provides that the number of shares available to grant under the 2017 Plan will increase each year by the lesser of (i) 1,200,000 shares, (ii) 4% of the Company’s common stock outstanding at December 31 of the immediately preceding year, or (iii) such number of shares as determined by the Board. As of June 30, 2023, 1,740,008 shares of common stock remained available for issuance under the 2017 Plan.

In November 2017, the Board adopted the 2017 Inducement Equity Incentive Plan (the “Inducement Plan”) and reserved 1,000,000 shares of the Company’s common stock for issuance pursuant to equity awards granted under the Inducement Plan. The Inducement Plan was adopted without stockholder approval.

The Inducement Plan has a 10-year term and provides for the grant of equity-based awards, including nonstatutory stock options, restricted stock units, restricted stock, stock appreciation rights, performance shares and performance units, and its terms are substantially similar to the 2017 Plan, including with respect to treatment of equity awards in the event of a “merger” or “change in control” as defined under the Inducement Plan. Options issued under the Inducement Plan may have a term up to ten years and have variable vesting provisions. New hire grants generally vest 25% per year starting upon the first anniversary of the grant. Equity-based awards issued under the Inducement Plan are only issuable to individuals not previously engaged as employees or as non-employee directors of the Company prior to the Inducement Plan’s adoption date. In May 2021, the Board approved an amendment to the Inducement Plan to reserve an additional 1,000,000 shares of the Company’s common stock for issuance pursuant to the Inducement Plan. As of June 30, 2023, 1,244,626 shares of common stock remained available for issuance under the Inducement Plan.

A summary of stock option activity under the 2015 Plan, 2017 Plan and Inducement Plan for the six-months ended June 30, 2023 is presented below:

	*Stock Options Outstanding*
	*Number of shares*			*Weighted average exercise price*		*Weighted average remaining life (in years)*
Balances — December 31, 2022		5,250,696		$	12.67		6.24
Options granted		2,242,386			5.12
Options exercised		(12,900	)		4.55
Options canceled		(165,394	)		6.59
Options expired		(426,773	)		13.01
Balances — June 30, 2023		6,888,015		$	10.35		7.40
Exercisable — June 30, 2023		3,589,647		$	14.23		5.58

Time-based Options

The Company awards time-based options which vest and become exercisable, subject to the individual’s continued employment or service through the applicable vesting date. Time-based options can have various vesting schedules, most commonly new hire grants which generally vest 25% per year starting upon the first anniversary of the grant.

A summary of the time-based stock option activity under the 2015 Plan, 2017 Plan and Inducement Plan for the six-months ended June 30, 2023 is presented below:

	*Stock Options Outstanding*
	*Number of shares*			*Weighted average exercise price*		*Weighted average remaining life (in years)*
Balances — December 31, 2022		4,730,394		$	12.95		6.16
Options granted		442,386			5.93
Options exercised		(12,900	)		4.55
Options canceled		(127,894	)		7.92
Options expired		(348,601	)		13.05
Balances — June 30, 2023		4,683,385		$	12.44		6.48
Exercisable — June 30, 2023		3,372,083		$	14.47		5.52

The fair value of the time-based options granted during the six-months ended June 30, 2023 was $2.0 million.

Performance-based Options

Certain stock options awarded by the Company contain performance conditions related to certain financial measures and achievements of strategic/operational milestones. The options will vest and become exercisable once the specific performance condition is fulfilled.

A summary of the performance-based option activity under the 2017 Plan and Inducement Plan for the six-months ended June 30, 2023 is presented below:

	*Stock Options Outstanding*
	*Number of shares*			*Weighted average exercise price*		*Weighted average remaining life (in years)*
Balances — December 31, 2022		520,302		$	10.08		7.02
Options granted		800,000			3.03
Options exercised		—			—
Options canceled		(37,500	)		2.05
Options expired		(78,172	)		12.84
Balances — June 30, 2023		1,204,630		$	5.47		8.93
Exercisable — June 30, 2023		217,564		$	10.55		6.47

The fair value of the performance-based options granted during the six-months ended June 30, 2023 was $1.9 million.

Market-based Options

Certain stock options awarded by the Company contain market conditions related to achievement of certain market capitalization targets. The options will vest and become exercisable once the specific market capitalization targets are fulfilled.

A summary of the market-based option activity under the 2017 Plan and Inducement Plan for the six-months ended June 30, 2023 is presented below:

	Stock Options Outstanding
	Number of shares		Weighted average exercise price		Weighted average remaining life (in years)
Balances — December 31, 2022		—	$	—		—
Options granted		1,000,000		6.44
Options exercised		—		—
Options canceled		—		—
Options expired		—		—
Balances — June 30, 2023		1,000,000	$	6.44		9.83
Exercisable — June 30, 2023		—		—		—

The fair value of the market-based options granted during the six-months ended June 30, 2023 was $4.8 million.

The Company estimates the fair value of time-based and performance-based stock options on the grant date using the Black-Scholes option pricing model. The estimated fair value of these employee stock options is amortized on a straight-line basis over the requisite service period of the awards. The Company reviews, and when deemed appropriate, updates the assumptions used on a periodic basis. The fair value of time-based and performance-based stock options was estimated using the following weighted-average assumptions:

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
Expected term in years		5.0 - 6.3		5.3 - 6.3		5.0 - 6.3		5.3 - 6.8
Expected volatility		89% - 94%		88%		89% - 94%		83% - 88%
Risk-free interest rate		3.8%		3.0%		3.8%		1.9% - 3.0%
Dividend yield		—		—		—		—

The Company estimates the fair value of market-based stock options on the grant date using a Monte Carlo simulation model. The estimated fair value of these employee stock options is amortized over the requisite service period for each tranche of the awards. The requisite service period is the service period derived from the Monte Carlo simulation model. If the market capitalization targets are met sooner than the derived service period, the Company will accelerate the recognition of stock-based compensation expense to reflect the cumulative expense associated with the vested shares. The fair value of market-based stock options was estimated using the following weighted-average assumptions:

	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Expected term in years		4.4 - 5.9		—		4.4 - 5.9		—
Expected volatility		90%		—		90%		—
Risk-free interest rate		3.4%		—		3.4%		—
Dividend yield		—		—		—		—

2017 Employee Stock Purchase Plan

The Board previously adopted, and the Company's stockholders approved, the Company’s 2017 Employee Stock Purchase Plan (the “2017 ESPP”).

The 2017 ESPP is a broad-based plan that provides employees of the Company and its designated affiliates with the opportunity to become stockholders through periodic payroll deductions that are applied towards the purchase of Company common shares at a discount from the then-current market price. Subject to adjustment in the case of certain capitalization events, a total of 250,000 common shares of the Company were available for purchase at adoption of the 2017 ESPP. Pursuant to the 2017 ESPP, the annual share increase pursuant to the evergreen provision is determined based on the least of (i) 450,000 shares, (ii) 1.5% of the Company’s common stock outstanding at December 31 of the immediately preceding year, or (iii) such number of shares as determined by the Board. The Board waived the evergreen provision for 2022 and 2023 and no additional shares were reserved under the 2017 ESPP. During the three months ended June 30, 2023, the Company did not issue any shares of common stock under the 2017 ESPP and during the six months ended June 30, 2023, the Company issued 262,470 shares of common stock under the 2017 ESPP. As of June 30, 2023, 198,529 shares of common stock remained available for issuance under the 2017 ESPP.

The Company estimates the fair value of ESPP grants on their grant date using the Black-Scholes option pricing model. The estimated fair value of ESPP grants is amortized on a straight-line basis over the requisite service period of the grants. The Company reviews, and when deemed appropriate, updates the assumptions used on a periodic basis. The Company utilizes its estimated volatility in the Black-Scholes option pricing model to determine the fair value of ESPP grants. The fair value of ESPP grants was estimated using the following weighted-average assumptions:

	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Expected term in years		0.5 - 1.0		0.5 - 1.0		0.5 - 1.0		0.5 - 1.0
Expected volatility		83%		83%		83%		83%
Risk-free interest rate		5.1% - 5.2%		0.6% - 0.9%		5.1% - 5.2%		0.6% - 0.9%
Dividend yield		—		—		—		—

Stock-based Compensation

Total stock-based compensation expense consisted of the following (in thousands):

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
Cost of revenues	$	—	$	90	$	—	$	180
Research and development		518		496		776		953
Sales and marketing		—		362		—		816
General and administrative		625		765		1,263		1,771
Total stock-based compensation expense	$	1,143	$	1,713	$	2,039	$	3,720

As of June 30, 2023, not all of the performance conditions of the performance options are probable to be achieved. Compensation expense has only been recognized for those conditions that are assumed to be probable.

Total stock-based compensation expense by type was as follows (in thousands):

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
Time-based options	$	876	$	1,445	$	1,554	$	3,252
Performance-based and market-based options		245		132		362		215
ESPP		22		136		123		253
Total stock-based compensation expense	$	1,143	$	1,713	$	2,039	$	3,720

Note 9 - Controlled Launch (Details Textual) $ in Thousands	3 Months Ended		6 Months Ended
Note 9 - Controlled Launch (Details Textual) $ in Thousands	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Feb. 28, 2021
Number of KOLs					70
Controlled Launch, Program Expenses	$ 0	$ 100	$ 0	$ 600
Revenue from Contract with Customer, Excluding Assessed Tax	$ 0	265	0	709
Redemption of Non Cash Credits [Member]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 100	$ 0	$ 400
Minimum [Member]
Number of Patients Participating in Procedure					40
Maximum [Member]
Number of Patients Participating in Procedure					50

Note 13 - Restructuring Charges (Details Textual) - Employee Severance [Member] $ in Millions	1 Months Ended
	Feb. 28, 2023 USD ($)	Mar. 31, 2022 USD ($)
Restructuring and Related Cost, Number of Positions Eliminated	7
Total Cost and Expenses [Member]
Restructuring Charges	$ 0.1
Total Cost and Expenses [Member] \| March 2022 Restructuring Plan [Member]
Restructuring Charges		$ 0.7

Note 13 - Restructuring Charges

6 Months Ended

Jun. 30, 2023

Restructuring and Related Activities Disclosure [Text Block]

13. Restructuring Charges

On March 31, 2022, the Company initiated a plan to reduce its operating expenses, preserve financial resources, and focus its sales and marketing efforts on increasing utilization of CellFX Systems. The Company’s Board of Directors approved changes to the Company’s commercial leadership, restructuring of its commercial field organization and reductions in other personnel and expenses across the Company. The Company announced a reduction in force effective as of March 31, 2022. The affected employees were offered separation benefits, including severance payments along with temporary healthcare coverage assistance. The Company incurred a discrete restructuring related charge of $0.7 million which was fully recorded in March 2022 and the related expenses are included within total cost and expenses on the condensed consolidated statement of operations for the six months ended June 30, 2022. This charge represents the total amount incurred in connection with the activity.

In February 2023, the Company eliminated an additional seven positions and incurred a discrete restructuring related charge of $0.1 million which was fully recorded in February 2023 and the related expenses are included within total cost and expenses on the condensed consolidated statement of operations for the six months ended June 30, 2023. This charge represents the total amount incurred in connection with the activity.

Note 6 - Stockholders' Equity and Stock-based Compensation - Stock-based Compensation Expense by Recorded Location (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Total stock-based compensation expense	$ 1,143	$ 1,143	$ 1,713	$ 2,039	$ 3,720
Cost of Sales [Member]
Total stock-based compensation expense		0	90	0	180
Research and Development Expense [Member]
Total stock-based compensation expense		518	496	776	953
Selling and Marketing Expense [Member]
Total stock-based compensation expense		0	362	0	816
General and Administrative Expense [Member]
Total stock-based compensation expense		$ 625	$ 765	$ 1,263	$ 1,771

Note 2 - Summary of Significant Accounting Policies - Warrant Accrual Activity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Beginning balance	$ 50	$ 97	$ 50	$ 80
Add: Accruals for warranties issued during the period	0	25	0	42
Less: Adjustment for inventory at cost	(50)	0	(50)	0
Ending balance	$ 0	$ 122	$ 0	$ 122

Note 6 - Stockholders' Equity and Stock-based Compensation - Option Assumptions (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Market-based Options [Member]
Expected volatility	90.00%	0.00%	90.00%	0.00%
Risk-free interest rate	3.40%	0.00%	3.40%	0.00%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Time-based and Performance Options [Member]
Expected volatility		88.00%
Risk-free interest rate	3.80%	3.00%	3.80%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Minimum [Member] \| Market-based Options [Member]
Expected term in years (Year)	4 years 4 months 24 days		4 years 4 months 24 days
Minimum [Member] \| Time-based and Performance Options [Member]
Expected term in years (Year)	5 years	5 years 3 months 18 days	5 years	5 years 3 months 18 days
Expected volatility	89.00%		89.00%	83.00%
Risk-free interest rate				1.90%
Maximum [Member] \| Market-based Options [Member]
Expected term in years (Year)	5 years 10 months 24 days		5 years 10 months 24 days
Maximum [Member] \| Time-based and Performance Options [Member]
Expected term in years (Year)	6 years 3 months 18 days	6 years 3 months 18 days	6 years 3 months 18 days	6 years 9 months 18 days
Expected volatility	94.00%		94.00%	88.00%
Risk-free interest rate				3.00%

Note 8 - Commitments and Contingencies

6 Months Ended

Jun. 30, 2023

Commitments and Contingencies Disclosure [Text Block]

8. Commitments and Contingencies

2022 Loan Agreement

On September 20, 2022, the Company and Robert W. Duggan, the Executive Chairman, entered into a Loan Agreement (“2022 Loan Agreement”) in connection with Mr. Duggan lending the principal sum of $65.0 million to the Company. The Loan Agreement bore interest at a rate per annum equal to 5.0%, payable quarterly commencing on January 1, 2023, with the principal sum payable on March 20, 2024. On March 17, 2023, the Company and Mr. Duggan amended certain terms of the Loan Agreement. There were no changes to the interest rate, but the principal sum repayment date was changed to September 30, 2024. During the six-month period ended June 30, 2023, the Company made cash payments of $1.7 million for accrued interest on the loan, and recorded an additional $1.1 million of interest expense in relation to the 2022 Loan Agreement. On April 30, 2023, the Company entered into a Securities Purchase Agreement with Mr. Duggan, pursuant to which the Company agreed to issue and sell to Mr. Duggan 10,022,937 shares of the Company’s common stock, par value $0.001 per share, in a Private Placement, at a price per share of $6.51. These shares were paid for through the cancellation of the amounts then owed by the Company under the 2022 Loan Agreement, the principal sum of $65.0 million and all accrued and unpaid interest outstanding, which totaled approximately $0.2 million as of April 30, 2023. The parties completed the Private Placement on May 9, 2023 and, upon closing and satisfaction of the outstanding debt, the 2022 Loan Agreement terminated, without early termination fees or penalties being owed by the Company. No additional amounts are owed to Mr. Duggan under the 2022 Loan Agreement.

Operating Leases

In January 2017, the Company entered into a five-year lease (the “Existing Lease”) for approximately 15,700 square feet for its corporate headquarters located in Hayward, California. The lease commenced in July 2017.

In May 2019, the Company entered into Lease Amendment 1 (the “Lease Amendment”) in relation to the Existing Lease and added the lease of new premises of approximately 13,300 square feet and 21,300 square feet, (“Expansion Premises 1” and “Expansion Premises 2”, respectively). Additionally, the term of the Existing Lease was extended to October 2029 to be coterminous with Expansion Premises 1 and Expansion Premises 2.

The Company evaluated the lease amendment under the provisions of ASC 842. It concluded that the Lease Amendment would be accounted for as a single contract with the Existing Lease because the additional lease payments due to the Lease Amendment was not commensurate with the right-of-use asset granted to the Company. Though the Lease Amendment was accounted for as a single contract, the Existing Premises, Expansion Premises 1 (occupied in November 2019) and Expansion Premises 2 (occupied in May 2020) are accounted for as separate lease components. Accordingly, the Company measured and allocated consideration to each lease component as of the modification date.

Supplemental balance sheet information related to leases (in thousands):

	*June 30,*		*December 31,*
Assets:	*2023*		*2022*
Right-of-use assets	$	7,670	$	8,062

	*June 30,*		*December 31,*
Liabilities:	*2023*		*2022*
Current operating lease liabilities	$	975	$	896
Non-current operating lease liabilities		8,644		9,144
Total lease liabilities	$	9,619	$	10,040

Total cash paid for operating lease liabilities (in thousands):

	*Six Months Ended June 30,*
	*2023*		*2022*
Cash paid for operating lease liabilities	$	907	$	894

Maturities of operating lease liabilities were as follows (in thousands):

Year ending December 31:
2023 (remaining 6 months)	$	937
2024		1,910
2025		1,977
2026		2,046
2027		2,117
Thereafter		4,075
Total lease payments		13,062
Less imputed interest		(3,443	)
Total lease liabilities	$	9,619

Weighted-average remaining lease term and discount rate, as of June 30, 2023, were as follows:

Weighted-average remaining lease term			6.34
Weighted-average discount rate			10	%

Rent expense, including common area maintenance charges, was approximately $0.5 million for each of the three-month periods ended June 30, 2023 and 2022; and was approximately $1.0 million for each of the six-month periods ended June 30, 2023 and 2022, respectively.

Legal Proceedings

From time to time, we may be involved in a variety of claims, lawsuits, investigations, and proceedings relating to securities laws, product liability, patent infringement, contract disputes, and other matters relating to various claims that arise in the normal course of our business, including the matter described below. The outcome of any legal proceedings is unpredictable but, regardless of outcome, they can have an adverse impact on us because of defense and settlement costs, diversion of management resources, negative publicity, reputational harm, and other factors. We maintain insurance that may provide coverage for such matters, including customary employment practices liability insurance.

In November 2022, the employment of our former Chief Financial Officer, Sandra Gardiner, terminated. Ms. Gardiner’s departure was not the result of any disagreement with the Company on any matter relating to its operations, accounting policies or practices, although the Company determined that she was not eligible to receive any severance benefits under the terms and conditions of her then existing employment agreement. In March 2023, Ms. Gardiner filed an arbitration demand with JAMS seeking severance benefits and other remedies, alleging breach of contract and unlawful termination in violation of public policy, among other things. We believe that Ms. Gardiner’s claims are without merit and we intend to vigorously defend ourselves against them. Because of the difficulty in predicting the outcome of any legal proceeding, particularly one that is in its early stages, the Company is not able to conclude that a liability is probable and cannot predict what the final outcome of Ms. Gardiner’s arbitration proceeding will likely be or provide a reasonable estimate for the range of ultimate possible loss, if any. However, at this time, we believe that the final resolution of this matter will not adversely affect our consolidated position, results of operations, or cash flows and that a liability is not probable at this time.

Note 6 - Stockholders' Equity and Stock-based Compensation - ESPP Assumptions (Details) - The 2017 Employee Stock Purchase Plan [Member]	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Expected volatility	83.00%	83.00%	83.00%	83.00%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Minimum [Member]
Expected term in years (Year)	6 months	6 months	6 months	6 months
Risk-free interest rate	5.10%	0.60%	5.10%	0.60%
Maximum [Member]
Expected term in years (Year)	1 year	1 year	1 year	1 year
Risk-free interest rate	5.20%	0.90%	5.20%	0.90%

Note 4 - Balance Sheet Components - Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Compensation expense	$ 2,123		$ 1,377
Director and officer liability insurance (Note 12)	0		571
Clinical trial fees and costs	49		64
Professional fees	503		318
Warranty	0	$ 50	50	$ 122	$ 97	$ 80
Other	169		215
Accrued Liabilities, Current	$ 2,844		$ 2,595

Note 2 - Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2023

Significant Accounting Policies [Text Block]

2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements have been prepared on a basis consistent with the Company’s December 31, 2022 audited Consolidated Financial Statements and include all adjustments, consisting of only normal recurring adjustments, necessary to fairly state the information set forth herein. The condensed consolidated financial statements have been prepared in accordance with the applicable rules and regulations of the Securities and Exchange Commission (the “SEC”) and, as permitted by such rules and regulations, omit certain information and footnote disclosures necessary to present the financial statements in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). The condensed consolidated balance sheet as of December 31, 2022 was derived from the audited consolidated financial statements as of that date but does not include all of the information and footnotes required by U.S. GAAP for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022. The results of operations for the three-month and six-month periods ended June 30, 2023, are not necessarily indicative of the results to be expected for the entire year or any future periods.

Principles of Consolidation

The accompanying condensed consolidated financial statements include the financial statements of Pulse Biosciences, Inc. and its wholly-owned subsidiaries. Intercompany balances and transactions, if any, have been eliminated in consolidation.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires the Company to make estimates and assumptions that affect the amounts reported in the Financial Statements and accompanying notes to the condensed consolidated financial statements. Estimates include, but are not limited to, the valuation of cash equivalents, the valuation and recognition of share-based compensation, income taxes, and the useful lives assigned to long-lived assets. The Company evaluates its estimates and assumptions based on historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ materially from these estimates.

Significant Accounting Policies

The Company’s significant accounting policies are described in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022. The Company continually evaluates the accounting policies and estimates used in preparing the consolidated financial statements. During the three-month period ended June 30, 2023, the Company issued stock options to certain employees which contain market conditions related to overall market cap. Additionally, the Company has issued stock options to certain employees which contain performance conditions related to certain financial measures and achievements of strategic/operational milestones.

Stock-Based Compensation

The Company's stock-based compensation programs include stock options and an employee stock purchase program. The Company accounts for stock-based compensation using the fair value method.

The Company periodically issues stock options to officers, directors, employees and consultants for services rendered. Such issuances vest and expire according to terms established at the issuance date. Stock-based payments to officers, directors and employees, including grants of employee stock options, are recognized in the financial statements based on their grant date fair values, which are estimated using the Black-Scholes option-pricing model. Stock-based compensation expense is charged to operations on a straight-line basis over the vesting period. The Company has granted stock options with both time-based as well as performance-based vesting conditions. For stock awards with performance-based vesting conditions, the Company does not recognize compensation expense until it is probable that the performance-based vesting condition will be achieved. The analysis to determine such probability involves estimates and judgements from management and the estimate of expense may be revised periodically.

The Company has also issued certain stock options with market-based vesting conditions. These vesting conditions relate to the achievement of certain market capitalization targets of the Company. The grant date fair value for these stock options was determined using a Monte Carlo simulation. The expense is recognized over the requisite service period for each tranche of the awards. The requisite service period is the service period derived from the Monte Carlo simulation model. If the market capitalization targets are met sooner than the derived service period, the Company will accelerate the recognition of stock-based compensation expense to reflect the cumulative expense associated with the vested shares. The Monte Carlo simulation requires the Company to make assumptions and judgements about the variables used in the calculation including the expected term, volatility of the Company's common stock, an assumed risk-free interest rate, and cost of equity. The assumptions used in the option-pricing model represent management’s best estimates. If factors change and different assumptions are used, the Company's stock-based compensation expense could be materially different in the future.

See Note 6 for a detailed discussion of the Company’s stock plans and stock-based compensation expense.

Valuation of Inventory

Inventory is stated at lower of cost or net realizable value. The Company establishes the inventory basis by determining the cost based on standard costs approximating the purchase costs on a first-in, first-out basis. Net realizable value is the estimated selling price in the ordinary course of the Company’s business, less reasonably predictable costs of completion, disposal, and transportation. The cost basis of the Company’s inventory will be reduced for any products that are considered excessive or obsolete based upon assumptions about future demand and market conditions. At December 31, 2022, the inventory balance was fully written off due to excessive and obsolete inventory and the Company does not plan to capitalize further inventory in relation to the dermatology market.

Revenue from Contracts with Customers

The Company recognized revenue at a point in time when it satisfied performance obligations by transferring control of promised goods to its customers. The amount of revenue recognized was equal to the consideration which the Company was entitled to in exchange for the promised goods, excluding any amounts assessed by government authorities for taxes which might have been collected from a customer. Sales contracts often involved the sale and delivery of multiple products, each of which typically represented a separate performance obligation in the contract. While the Company has sold these products on a stand-alone basis at their respective stand-alone selling prices (“SSP”), initial customer contracts primarily involved the bundling of products which were delivered concurrently to the customer. In such instances, the full consideration of the contract was recognized upon shipment of the products. The Company generally required receipt of full payment prior to shipment, however, from time to time, payment terms were extended to customers upon which the Company performed a necessary credit evaluation to ensure future collectability of the outstanding balance. The accounts receivable balance at June 30, 2023 is zero and the Company has therefore not recorded an allowance against the accounts receivable balance. Refer to Note 10 for further details.

Product Warranty

The Company provides a standard warranty on eligible products which provides the customer assurances that the products comply with the agreed-upon specifications. The standard warranty does not provide any services in addition to those assurances. The Company accrued a warranty reserve for products sold based upon the best estimate of the nature, frequency, and costs of future claims. These estimates are inherently uncertain given the short history of sales, and changes to the historical or projected warranty experience may cause material changes to the warranty reserve in the future. During the three-month period ended June 30, 2023, the Company reduced the accrued warranty liability to zero. Based upon the Company's shift in focus, there are a limited number of consoles currently covered under the standard warranty. All inventory has been fully written off, therefore the only incremental costs to fulfill a warranty claim would be shipping costs, which will be immaterial in nature.

Warranty accrual activity consisted of the following for the three-month and six-month periods ended June 30, 2023 and 2022 (in thousands):

	*Three Months Ended June 30,*					*Six Months Ended June 30,*
	*2023*			*2022*		*2023*			*2022*
Beginning balance	$	50		$	97	$	50		$	80
Add: Accruals for warranties issued during the period		—			25		—			42
Less: Adjustment for inventory at cost		(50	)		—		(50	)		—
Ending balance	$	—		$	122	$	—		$	122

Net Loss per Share

The Company calculates basic net loss per share by dividing net loss by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed by giving effect to all potential dilutive common stock equivalents outstanding during the period. For purposes of this calculation, options to purchase common stock and common stock warrants are considered common stock equivalents. Potential common shares that have an anti-dilutive effect (i.e., those that increase income per share or decrease loss per share) are excluded from the calculation of diluted net loss per share.

Basic and diluted net loss per common share is the same for all periods presented because all warrants, stock options and restricted stock units outstanding are anti-dilutive.

The following outstanding stock options, and warrants were excluded from the computation of diluted net loss per share for the periods presented because including them would have had an anti-dilutive effect:

	*Six Months Ended June 30,*
	*2023*		*2022*
Common stock warrants		—		7,310,917
Common stock options		6,888,015		5,608,140
Total		6,888,015		12,919,057

Recent Accounting Pronouncements

There are no recent accounting pronouncements that impact the Company’s operations.

Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2023

Accounting Policies [Abstract]

Basis of Accounting, Policy [Policy Text Block]

Basis of Presentation

Consolidation, Policy [Policy Text Block]

Principles of Consolidation

Use of Estimates, Policy [Policy Text Block]

Use of Estimates

Share-Based Payment Arrangement [Policy Text Block]

Stock-Based Compensation

The Company's stock-based compensation programs include stock options and an employee stock purchase program. The Company accounts for stock-based compensation using the fair value method.

See Note 6 for a detailed discussion of the Company’s stock plans and stock-based compensation expense.

Inventory, Policy [Policy Text Block]

Valuation of Inventory

Revenue from Contract with Customer [Policy Text Block]

Revenue from Contracts with Customers

Standard Product Warranty, Policy [Policy Text Block]

Product Warranty

Warranty accrual activity consisted of the following for the three-month and six-month periods ended June 30, 2023 and 2022 (in thousands):

	*Three Months Ended June 30,*					*Six Months Ended June 30,*
	*2023*			*2022*		*2023*			*2022*
Beginning balance	$	50		$	97	$	50		$	80
Add: Accruals for warranties issued during the period		—			25		—			42
Less: Adjustment for inventory at cost		(50	)		—		(50	)		—
Ending balance	$	—		$	122	$	—		$	122

Earnings Per Share, Policy [Policy Text Block]

Net Loss per Share

Basic and diluted net loss per common share is the same for all periods presented because all warrants, stock options and restricted stock units outstanding are anti-dilutive.

	*Six Months Ended June 30,*
	*2023*		*2022*
Common stock warrants		—		7,310,917
Common stock options		6,888,015		5,608,140
Total		6,888,015		12,919,057

New Accounting Pronouncements, Policy [Policy Text Block]

Recent Accounting Pronouncements

There are no recent accounting pronouncements that impact the Company’s operations.

Note 4 - Balance Sheet Components - Schedule of Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
2023 (remaining 6 months)	$ 333
2024	665
2025	665
2026	555
Finite-Lived Intangible Assets, Net	$ 2,218	$ 2,551

Note 12 - Related Party Transactions

6 Months Ended

Jun. 30, 2023

12. Related Party Transactions

In May 2022, the Company determined not to renew its annual director and officer liability insurance policy due to disproportionately high premiums quoted by insurance companies. Instead, on May 31, 2022, the Company and Robert W. Duggan, majority stockholder and Executive Chairman, entered into a letter agreement (the “Letter Agreement”) pursuant to which Mr. Duggan agreed with the Company to personally provide indemnity coverage for a one-year period, and he agreed to deposit cash and/or marketable securities into a third-party escrow, as security for these obligations, if requested by the Company. On May 31, 2023, the last day of the one-year period, the Company paid Mr. Duggan a fee of $1.0 million in consideration of the obligations set forth in the Letter Agreement. As of June 30, 2023, there were no additional amounts owed to Mr. Duggan under the Letter Agreement.

On September 20, 2022, the Company and Robert W. Duggan, majority stockholder and Executive Chairman, entered into the 2022 Loan Agreement in connection with Mr. Duggan lending the principal sum of $65.0 million to the Company. On April 30, 2023, the Company entered into a Securities Purchase Agreement with Mr. Duggan, pursuant to which the Company agreed to issue and sell to Mr. Duggan 10,022,937 shares of the Company’s common stock, par value $0.001 per share, in a Private Placement, at a price per share of $6.51. These shares were paid for through the cancellation of the amounts then owed by the Company under the 2022 Loan Agreement, the principal sum of $65.0 million and all accrued and unpaid interest outstanding, which totaled approximately $0.2 million as of April 30, 2023. Upon closing of the Private Placement and satisfaction of the outstanding debt, the 2022 Loan Agreement terminated, without early termination fees or penalties being owed by the Company. No additional amounts are owed to Mr. Duggan under the 2022 Loan Agreement. See Note 8 for further details.

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Note 8 - Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2023

Schedule of Information Related to Right-of-use Assets and Lease Liabilities [Table Text Block]

	*June 30,*		*December 31,*
Assets:	*2023*		*2022*
Right-of-use assets	$	7,670	$	8,062

	*June 30,*		*December 31,*
Liabilities:	*2023*		*2022*
Current operating lease liabilities	$	975	$	896
Non-current operating lease liabilities		8,644		9,144
Total lease liabilities	$	9,619	$	10,040

	*Six Months Ended June 30,*
	*2023*		*2022*
Cash paid for operating lease liabilities	$	907	$	894

Year ending December 31:
2023 (remaining 6 months)	$	937
2024		1,910
2025		1,977
2026		2,046
2027		2,117
Thereafter		4,075
Total lease payments		13,062
Less imputed interest		(3,443	)
Total lease liabilities	$	9,619

Weighted-average remaining lease term			6.34
Weighted-average discount rate			10	%

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net loss	$ (19,711)	$ (31,269)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	271	347
Amortization of intangible assets	333	333
Stock-based compensation	2,039	3,720
Changes in operating assets and liabilities:
Accounts receivable	0	53
Inventory	0	(2,047)
Prepaid expenses and other current assets	(309)	1,112
Other receivables	106	(30)
Right-of-use assets	392	352
Accounts payable	212	(931)
Accrued expenses	239	296
Deferred revenue	0	16
Lease liabilities	(421)	(369)
Accrued interest on related party note payable	1,077	0
Accrued interest on note payable	0	1
Net cash used in operating activities	(15,772)	(28,416)
Cash flows from investing activities:
Purchases of property and equipment	(55)	(298)
Net cash used in investing activities	(55)	(298)
Cash flows from financing activities:
Proceeds from issuance of common stock under employee stock purchase plan	292	372
Proceeds from issuance of common stock	0	14,963
Proceeds from exercises of warrants	14,835	0
Proceeds from exercises of stock options	58	0
Payments made on insurance loan agreement	0	(437)
Issuance cost in relation to related party note extinguishment	(5)	0
Payments made on related party note	(1,745)	0
Net cash provided by financing activities	13,435	14,898
Net decrease in cash and cash equivalents	(2,392)	(13,816)
Cash and cash equivalents at beginning of period	61,139	28,614
Cash and cash equivalents at end of period	58,747	14,798
Supplemental disclosure of noncash investing and financing activities:
Principal and accrued interest of related party note settled via issuance of common stock	65,248	0
Equipment purchases included in accounts payable and accrued expenses	10	(27)
Other receivable from issuance of common stock	0	13
Issuance costs in accounts payable and accrued expenses	$ (8)	$ (74)

Note 6 - Stockholders' Equity and Stock-based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
Cost of revenues	$	—	$	90	$	—	$	180
Research and development		518		496		776		953
Sales and marketing		—		362		—		816
General and administrative		625		765		1,263		1,771
Total stock-based compensation expense	$	1,143	$	1,713	$	2,039	$	3,720

Share-Based Payment Arrangement, Cost by Plan [Table Text Block]

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
Time-based options	$	876	$	1,445	$	1,554	$	3,252
Performance-based and market-based options		245		132		362		215
ESPP		22		136		123		253
Total stock-based compensation expense	$	1,143	$	1,713	$	2,039	$	3,720

Share-Based Payment Arrangement, Option [Member]

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	*Three Months Ended June 30,*				*Six Months Ended June 30,*
	*2023*		*2022*		*2023*		*2022*
Expected term in years		5.0 - 6.3		5.3 - 6.3		5.0 - 6.3		5.3 - 6.8
Expected volatility		89% - 94%		88%		89% - 94%		83% - 88%
Risk-free interest rate		3.8%		3.0%		3.8%		1.9% - 3.0%
Dividend yield		—		—		—		—

	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Expected term in years		4.4 - 5.9		—		4.4 - 5.9		—
Expected volatility		90%		—		90%		—
Risk-free interest rate		3.4%		—		3.4%		—
Dividend yield		—		—		—		—

Market-based Options [Member]

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

	Stock Options Outstanding
	Number of shares		Weighted average exercise price		Weighted average remaining life (in years)
Balances — December 31, 2022		—	$	—		—
Options granted		1,000,000		6.44
Options exercised		—		—
Options canceled		—		—
Options expired		—		—
Balances — June 30, 2023		1,000,000	$	6.44		9.83
Exercisable — June 30, 2023		—		—		—

Performance Options [Member]

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

	*Stock Options Outstanding*
	*Number of shares*			*Weighted average exercise price*		*Weighted average remaining life (in years)*
Balances — December 31, 2022		520,302		$	10.08		7.02
Options granted		800,000			3.03
Options exercised		—			—
Options canceled		(37,500	)		2.05
Options expired		(78,172	)		12.84
Balances — June 30, 2023		1,204,630		$	5.47		8.93
Exercisable — June 30, 2023		217,564		$	10.55		6.47

Time-based Options [Member]

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

	*Stock Options Outstanding*
	*Number of shares*			*Weighted average exercise price*		*Weighted average remaining life (in years)*
Balances — December 31, 2022		4,730,394		$	12.95		6.16
Options granted		442,386			5.93
Options exercised		(12,900	)		4.55
Options canceled		(127,894	)		7.92
Options expired		(348,601	)		13.05
Balances — June 30, 2023		4,683,385		$	12.44		6.48
Exercisable — June 30, 2023		3,372,083		$	14.47		5.52

The 2017 Employee Stock Purchase Plan [Member]

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Expected term in years		0.5 - 1.0		0.5 - 1.0		0.5 - 1.0		0.5 - 1.0
Expected volatility		83%		83%		83%		83%
Risk-free interest rate		5.1% - 5.2%		0.6% - 0.9%		5.1% - 5.2%		0.6% - 0.9%
Dividend yield		—		—		—		—

The 2015 Plan, 2017 Plan and Inducement Plan [Member]

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

	*Stock Options Outstanding*
	*Number of shares*			*Weighted average exercise price*		*Weighted average remaining life (in years)*
Balances — December 31, 2022		5,250,696		$	12.67		6.24
Options granted		2,242,386			5.12
Options exercised		(12,900	)		4.55
Options canceled		(165,394	)		6.59
Options expired		(426,773	)		13.01
Balances — June 30, 2023		6,888,015		$	10.35		7.40
Exercisable — June 30, 2023		3,589,647		$	14.23		5.58

Document And Entity Information - shares	6 Months Ended
Document And Entity Information - shares	Jun. 30, 2023	Jul. 31, 2023
Document Information [Line Items]
Entity Central Index Key	0001625101
Entity Registrant Name	Pulse Biosciences, Inc.
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2023
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	001-34899
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-5696597
Entity Address, Address Line One	3957 Point Eden Way
Entity Address, City or Town	Hayward
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94545
City Area Code	510
Local Phone Number	906-4600
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	PLSE
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		54,902,942

Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares shares in Thousands	Jun. 30, 2023	Dec. 31, 2022
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	50,000	50,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	500,000	500,000
Common stock, shares issued (in shares)	54,771	37,235
Common stock, shares outstanding (in shares)	54,771	37,235

Note 4 - Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Property and equipment, gross	$ 4,979	$ 4,914
Less: Accumulated depreciation and amortization	(3,224)	(2,953)
Property and equipment, net	1,755	1,961
Leasehold Improvements [Member]
Property and equipment, gross	2,519	2,519
Laboratory Equipment [Member]
Property and equipment, gross	1,188	1,118
Furniture and Fixtures [Member]
Property and equipment, gross	966	966
Software and Software Development Costs [Member]
Property and equipment, gross	296	289
Construction in Progress [Member]
Property and equipment, gross	$ 10	$ 22

Note 8 - Commitments and Contingencies (Details Textual) $ / shares in Units, $ in Millions		3 Months Ended		6 Months Ended
	Apr. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2023 USD ($) $ / shares	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) $ / shares	Jun. 30, 2022 USD ($)	Dec. 31, 2022 $ / shares	Sep. 20, 2022 USD ($)	May 31, 2019 a	Jul. 31, 2017 a
Common Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares		$ 0.001		$ 0.001		$ 0.001
Operating Lease, Expense		$ 0.5	$ 0.5	$ 1.0	$ 1.0
Corporate Headquarters in Hayward, California [Member]
Lessee, Operating Lease, Term of Contract (Year)									5 years
Area of Real Estate Property (Acre) \| a									15,700
Corporate Headquarters in Hayward, California [Member] \| Expansion Premises 1 [Member]
Area of Real Estate Property (Acre) \| a								13,300
Corporate Headquarters in Hayward, California [Member] \| Expansion Premises 2 [Member]
Area of Real Estate Property (Acre) \| a								21,300
Robert W. Duggan [Member] \| Private Placement [Member]
Stock Issued During Period, Shares, New Issues (in shares) \| shares	10,022,937
Common Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares	$ 0.001
Shares Issued, Price Per Share (in dollars per share) \| $ / shares	$ 6.51
Two Thousand Twenty Two Loan Agreement [Member] \| Robert W. Duggan [Member]
Debt Instrument, Face Amount							$ 65.0
Debt Instrument Quarterly Interest Rate							5.0
Debt Instrument, Increase, Accrued Interest				1.7
Interest Expense				$ 1.1
Loan Agreement [Member]
Debt Instrument, Decrease, Forgiveness	$ 65.0
Interest Payable	$ 0.2

Note 11 - Segment Reporting - Revenue by Product (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Total revenues	$ 0	$ 265	$ 0	$ 709
System Products [Member]
Total revenues	0	209	0	576
Cycle Units Products [Member]
Total revenues	$ 0	$ 56	$ 0	$ 133

Note 10 - Revenue

6 Months Ended

Jun. 30, 2023

Revenue from Contract with Customer [Text Block]

10. Revenue

The Company recognized revenue at a point in time when it satisfied performance obligations by transferring control of promised goods to its customers. The amount of revenue recognized was equal to the consideration which the Company was entitled to in exchange for the promised goods, excluding any amounts assessed by government authorities for taxes which might be collected from a customer. This consideration may include non-cash services performed, as was the case with revenue recognized in connection with the Controlled Launch program. On September 20, 2022, the Company announced its shift in focus to advance its core NPS technology outside of dermatology and concluded its Controlled Launch program. The Company has not recognized any revenue during the three-month and six-month periods ended June 30, 2023. Total revenue recognized for the three-month and six-month periods ended June 30, 2022, was $0.3 million and $0.7 million, respectively, of which approximately $0.1 million and $0.4 million, respectively, was driven by the redemption of non-cash credits earned as part of the Controlled Launch, with the balances driven by cash purchases of cycle units (“CUs”) and CellFX commercial consoles sold.

Sales contracts often involve the sale and delivery of multiple performance obligations in the contract.

Performance Obligations

Systems consist of the CellFX console and its embedded software, handpieces, and disposable tips. The console is a physical piece of hardware used by the customer to perform patient procedures. Individually the console and software are not distinct, therefore the Company combines the console and embedded software to form one distinct system performance obligation. Payment for systems is generally due prior to shipment, and the system performance obligation is satisfied upon shipment of the system to the customer.

Handpieces are attached to the console and used in conjunction with tips to perform patient procedures. Generally, upon initial sale of a system to a customer, the Company will include two handpieces. The handpiece has a shorter expected useful life than the console, and a customer can purchase additional handpieces when needed, as they are available for sale on a stand-alone basis. Payment for handpieces is generally due prior to shipment, and handpieces represent a distinct performance obligation which is satisfied either upon shipment, or upon delivery of the handpiece to the customer, depending on the specific contract.

Disposable treatment tips are single-patient multiple-use products that come in different sizes, each of which are to be used for specific procedures. Tips are attached to the handpiece for use in patient procedures and, upon detachment from the handpiece, a tip cannot be reused, and it must be disposed of. Tips represent a distinct performance obligation which is satisfied either upon shipment, or upon delivery of the tips to the customer, depending on the specific contract.

CUs are credits that authorize the customer to perform a procedure, or cycle. Each procedure requires a specific number of CUs, dependent upon type of tip used and procedure level selected. As the procedure is performed, the applicable number of CUs are decremented. When the customer’s balance of CUs on a specific system is depleted, the system will no longer function until the customer purchases additional CUs. Customers can purchase additional CUs via the Company’s CellFX Marketplace which is an online marketplace accessible directly from the CellFX System. Payment for CUs is due upon order placement and the CUs are immediately available for download to the console via CellFX CloudConnect. CUs represent a distinct performance obligation which is satisfied when CUs are made available for customers to download from the Company’s CellFX CloudConnect, as customers can use purchased CUs at any time at their discretion, and the Company does not provide any ongoing service or other forms of involvement after the sale occurs.

Shipping and handling activities are not considered to be a separate performance obligation. The Company’s standard commercial agreements generally include FOB shipping point terms. The Company has made an accounting policy election to account for shipping and handling costs as fulfillment costs because the shipping and handling activities occur after the customer obtains control of the product.

Transaction Price

The transaction price is the consideration to which the Company expects to be entitled to in exchange for providing the promised goods to customers. Customer orders placed for cash contemplate a fixed amount of consideration. Customer orders placed by physicians participating in the Controlled Launch when they elected to purchase the CellFX System were paid for via conversion of accumulated earned credits for prior services provided by the physicians under the terms of their participation in the Controlled Launch. For these transactions, the transaction price included noncash consideration. The services rendered by the physicians in the Controlled Launch were accounted for separately from the subsequent sales of the CellFX Systems because they were distinct from the system sales. They were distinct because they provided the Company with treatment data that could also be procured, and historically had been procured by the Company, without the corresponding system sales. This data was used by the Company to enhance marketing and promotion of its products.

The Company evaluates the possible impact of variable consideration in determining the transaction price, in particular the possibility of future returns or credits. Sales agreements allow for a right of return only if the product does not conform to the agreed upon quality standards or if the product was shipped due to Company error. The Company anticipates such returns will be minimal and has made no adjustments to the transaction price for any estimated returns. The transaction price is determined at the time of the initial revenue recognition and updated each quarter for any changes in circumstances (e.g., changes in estimated return or credit rates).

The Company has made an accounting policy election to exclude from the measurement of the transaction price all taxes which are imposed on and concurrent with a specific revenue-producing transaction and collected by the entity from a customer.

When there are multiple performance obligations present, the total transaction price shall be allocated to each of the performance obligations based upon the relative SSPs of those performance obligations. The Company establishes SSPs based on multiple factors including, prices charged by the Company for similar offerings, product-specific business objectives, and the estimated cost to provide the performance obligation. However, upon the sale of a new CellFX System, all performance obligations are delivered concurrently and therefore there is no impact to revenue recognition timing, and the Company has determined allocations are not necessary. Should the customer purchase additional CUs, handpieces, or tips at a later time, those purchases will be made under separate purchase agreements, with all promised goods generally transferred at the same time, therefore no price allocation is necessary in that scenario either.

Controlled Launch Agreements

In August 2021, the Company began to recognize revenue in relation to the conversion of Controlled Launch Program participants into sales agreements (Note 9). These customers were already in possession of the system, handpiece, and tips. As such, upon execution of these purchase agreements, the Company recognized revenue on the agreements because control of all performance obligations were transferred at that time. These customers separately purchased CUs in order to operate the CellFX System and the revenue for these CUs was recognized upon delivery of the CUs to CellFX CloudConnect.

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

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