Semler Scientific (SMLR) 10-K 6 Mar 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2023	Mar. 01, 2024	Jun. 30, 2023
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	001-36305
Entity Registrant Name	SEMLER SCIENTIFIC, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-1367393
Entity Address, Address Line One	2340-2348 Walsh Avenue, Suite 2344
Entity Address, City or Town	Santa Clara
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95051
City Area Code	877
Local Phone Number	774-4211
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	SMLR
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
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
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 114,785,516
Entity Common Stock, Shares Outstanding		7,031,083
Auditor Name	BDO USA, P.C.
Auditor Firm ID	243
Auditor Location	New York, NY
Entity Central Index Key	0001554859
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false

Balance Sheets

Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current Assets:
Cash and cash equivalents	$ 57,200	$ 23,014
Restricted cash	132
Short-term investments		20,073
Trade accounts receivable, net of allowance for credit losses of $287 and $109, respectively	6,125	3,884
Inventory, net	445	469
Prepaid expenses and other current assets	2,042	1,468
Total current assets	65,944	48,908
Assets for lease, net	2,285	2,478
Property and equipment, net	720	667
Long-term investments	512	821
Notes held for investment (includes measured at fair value of $4,372 and $3,679, respectively)	5,372	4,679
Other non-current assets	270	2,842
Deferred tax assets	2,962	2,298
Total assets	78,065	62,693
Current liabilities:
Accounts payable	402	835
Accrued expenses	4,502	4,748
Deferred revenue	1,120	1,160
Other short-term liabilities	176	114
Total current liabilities	6,200	6,857
Long-term liabilities:
Other long-term liabilities	70	160
Total long-term liabilities	70	160
Commitments and contingencies (Note 13)
Stockholders' equity:
Common stock, $0.001 par value; 50,000,000 shares authorized; 7,099,441 and 6,906,544 shares issued, and 6,885,019 and 6,692,122 shares outstanding (treasury shares of 214,422 and 214,422), respectively	7	7
Additional paid-in capital	11,985	16,449
Retained earnings	59,803	39,220
Total stockholders' equity	71,795	55,676
Total liabilities and stockholders' equity	$ 78,065	$ 62,693

Balance Sheets (Parenthetical)

Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Balance Sheets
Allowance for credit losses (in dollars)	$ 287	$ 109
Notes, Fair value	$ 4,372	$ 3,679
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	7,099,441	6,906,544
Common stock, shares outstanding	6,885,019	6,692,122
Treasury stock, shares	214,422	214,422

Statements of Income

Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Statements of Income
Revenues	$ 68,184	$ 56,686
Operating expenses:
Cost of revenues	6,984	4,252
Engineering and product development	5,773	4,809
Sales and marketing	18,147	17,685
General and administrative	14,290	12,737
Strategic streamlining	734
Total operating expenses	45,928	39,483
Income from operations	22,256	17,203
Interest and dividend income	2,471	494
Impairment of investments	(337)
Change in fair value of notes held for investment	(307)
Other income (expenses)	17	(5)
Other income, net	1,844	489
Pre-tax income	24,100	17,692
Income tax provision	3,517	3,367
Net income	$ 20,583	$ 14,325
Net income per share, basic	$ 3.06	$ 2.13
Weighted average number of shares used in computing basic net income per share	6,732,806	6,726,687
Net income per share, diluted	$ 2.63	$ 1.79
Weighted average number of shares used in computing diluted net income per share	7,819,159	7,999,750

Statements of Stockholders' Equ

Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Total
Balance at Dec. 31, 2021	$ 7		$ 20,645	$ 24,895	$ 45,547
Balance (in shares) at Dec. 31, 2021	6,824,380
Balance (in shares) at Dec. 31, 2021		(65,922)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury stock acquired			(4,991)		$ (4,991)
Treasury stock acquired (in shares)		(148,500)			(148,500)
Employee stock grants			723		$ 723
Employee stock grants (in shares)	11,131
Taxes paid related to settlement of equity awards			(114)		(114)
Taxes paid related to settlement of equity awards (in shares)	(1,710)
Stock option exercises			168		168
Stock option exercises (in shares)	72,743
Stock-based compensation			18		18
Net income				14,325	14,325
Balance at Dec. 31, 2022	$ 7		16,449	39,220	$ 55,676
Balance (in shares) at Dec. 31, 2022	6,906,544
Balance (in shares) at Dec. 31, 2022		(214,422)			(214,422)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock warrants acquired			(1,949)		$ (1,949)
Employee stock grants			860		860
Employee stock grants (in shares)	24,295
Taxes paid related to settlement of equity awards			(3,510)		(3,510)
Taxes paid related to settlement of equity awards (in shares)	(114,970)
Stock option exercises			51		$ 51
Stock option exercises (in shares)	283,572				283,562
Stock-based compensation			84		$ 84
Net income				20,583	20,583
Balance at Dec. 31, 2023	$ 7		$ 11,985	$ 59,803	$ 71,795
Balance (in shares) at Dec. 31, 2023	7,099,441
Balance (in shares) at Dec. 31, 2023		(214,422)			(214,422)

Statements of Cash Flows

Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 20,583	$ 14,325
Reconciliation of Net Income to Net Cash Provided by Operating Activities:
Depreciation	599	589
Deferred tax expense	(664)	(351)
Loss on disposal of assets for lease	369	463
Write off of prepaid software licenses	2,476
Gain on short-term investments	(151)	(77)
Allowance for credit losses	268	103
Change in fair value of notes held for investment	307
Stock-based compensation	944	741
Impairment of long term investments	337
Changes in Operating Assets and Liabilities:
Trade accounts receivable	(2,508)	(367)
Inventory	24	81
Prepaid expenses and other current assets	(603)	2,576
Other non-current assets	96	(2,510)
Accounts payable	(433)	392
Accrued expenses	(246)	1,310
Other current and non-current liabilities	(68)	188
Net Cash Provided by Operating Activities	21,330	17,463
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property and equipment	(345)	(476)
Notes receivable	(1,000)
Proceeds from maturities of short-term investments	78,093	(4,679)
Purchase of short-term investments	(57,869)	(19,996)
Purchase of assets for lease	(483)	(1,684)
Net Cash Provided by (Used in) Investing Activities	18,396	(26,835)
CASH FLOWS FROM FINANCING ACTIVITIES:
Taxes paid related to net settlement of equity awards	(3,510)	(114)
Common stock warrants acquired	(1,949)
Treasury stock acquired		(4,991)
Proceeds from exercise of stock options	51	168
Net Cash Used in Financing Activities	(5,408)	(4,937)
INCREASE (DECREASE) IN CASH	34,318	(14,309)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	23,014	37,323
CASH, CASH EQUIVALENTS AND RESTRICTED CASH, END OF PERIOD	57,332	23,014
Supplemental Disclosure of Cash Flow Information:
Cash paid for taxes	$ 4,060	$ 2,400

The Company

The Company	12 Months Ended
	Dec. 31, 2023
The Company
The Company	1. The Company Semler Scientific Inc. (the “Company”) is a company providing technology solutions to improve the clinical effectiveness and efficiency of healthcare providers. The Company’s mission is to develop, manufacture and market innovative products and services that assist our customers in evaluating and treating chronic diseases. The Company’s patented and U.S. Food and Drug Administration (“FDA”), cleared product, QuantaFlo, measures arterial blood flow in the extremities to aid in the diagnosis of peripheral arterial disease (“PAD”). The Company is currently seeking a new 510(k) clearance from the FDA for the expanded use of QuantaFlo, which is intended to enable expanded labeling as an aid in the diagnosis of other cardiovascular diseases in addition to PAD.

Summary of Significant Accounti

Summary of Significant Accounting Policies and Estimates	12 Months Ended
	Dec. 31, 2023
Accounting Policies Abstract
Summary of Significant Accounting Policies and Estimates	2. Summary of Significant Accounting Policies and Estimates Basis for Presentation The Company’s financial statements and accompanying notes are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Use of Estimates The preparation of the accompanying financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities at the date of the financial statements, and reported amounts of revenues and expenses, and related disclosures during the reporting period. Significant items subject to such estimates include allowance for credit losses, valuation of equipment on lease, recognition and measurement of current and deferred income taxes, valuation and recognition of investments and valuation of inventory. These estimates and assumptions are based on management’s best estimates and judgment. Management regularly evaluates its estimates and assumptions using historical experience and other factors; however, actual results could differ significantly from these estimates. Concentration of Credit Risk ​ Financial instruments that potentially subject the Company to concentrations of credit risk primarily consist of cash, cash equivalents, restricted cash, accounts receivable and trade payables. The Company maintains its cash with major financial institutions. The Company’s cash consists of bank deposits held with banks that, at times, exceed federally insured limits. The cash and cash equivalents also include short term treasury bills with original maturities of three months or less and U.S. government money market fund accounts. The Company manages its accounts receivable credit risk through ongoing credit evaluation of its customers’ financial conditions. The Company generally does not require collateral from its customers. For information regarding the Company’s significant customers and vendors, see Note 11 to financial statements. ​ Revenue Recognition The Company generates revenues primarily from the rental or license of its vascular testing product. The Company recognizes revenues from the licensing of its product primarily pursuant to agreements that automatically renew each month with revenue recognized on a daily convention basis or when the test is performed. The Company’s arrangements with customers for its vascular testing product are normally on a month-to-month basis with fees billed at the rates established in the customer agreement, either on a fixed or variable (e.g. fee per test) basis, as earned. The Company also recognizes revenue for hardware and supplies sales as of the date of shipment. Shipping and handling costs are included in cost of revenues in the statement of income. Cash and Cash Equivalents Cash and cash equivalents are comprised of highly liquid investments purchased with an initial maturity date of three months or less. Funds held as investments in money market funds are included within cash and cash equivalents. Short-Term Investments Short-term investments are those that can be readily converted into cash and also any investment instruments that will mature within one year or which are expected to be liquidated within one year. Accounts Receivable and Allowance for Credit Losses Accounts receivables are recorded at the invoiced amount, net of allowances for credit losses. T he allowance for credit losses is based on management’s assessment of the collectability of accounts. The Company regularly reviews the adequacy of this allowance for credit losses by considering historical experience, the age of the accounts receivable balances, the credit quality of the customers, current economic conditions, reasonable and supportable forecasts of future economic conditions, and other factors that may affect customers’ ability to pay to determine whether a specific reserve is appropriate. Accounts receivable deemed uncollectable are charged against the allowance for credit losses when identified. ​ As of December 31, 2023, the allowance for credit losses was $287. Net change due to credit losses during the year was $178. Allowance balance as of December 31, 2022, was $109. Inventory Inventory, which is made up of finished goods, is recorded at the lower of cost or net realizable value. Cost is determined on the first-in, first-out method. The Company periodically analyzes its inventory levels to identify inventory that has a cost basis in excess of its estimated realizable value, and writes down such inventory as appropriate. Assets for Lease Assets for lease are recorded at cost. At December 31, 2023 and 2022, assets for lease consisted of vascular testing devices, which are primarily leased to customers. The cost of such assets for lease is depreciated on a straight-line basis over 36 months for the units outstanding and recorded as cost of revenues. The Company regularly reviews whether facts and circumstances exist which indicate that the carrying amounts of assets, may not be recoverable or that the useful life of assets are shorter or longer than originally estimated. The Company assesses the recoverability of its assets by comparing the projected undiscounted net cash flows associated with the related assets over their estimated remaining lives against their respective carrying amounts. The Company considers factors such as estimated usage and expected lives of its assets for lease in this analysis. Impairment, if any, is based on the excess of the carrying amount over the fair value of those assets. At December 31, 2023 and 2022, there were no impairment indicators. Property and Equipment Capital assets are recorded at cost. The cost of such capital assets is depreciated on a straight-line basis over a term depending on the assigned category (described below) and recorded as depreciation for capital assets recorded in engineering and product development, sales and marketing and general and administrative expenses. At December 31, 2023 and 2022, capital assets are classified into one of the following categories: ​ ​ ​ Category Name Description Machinery & Equipment ​ Manufacturing, R&D, or other non-office equipment Computer Equipment & Software ​ Software, computers, monitors, printers and other related equipment. Furniture & Fixtures ​ Office equipment and furniture owned by the company ​ At December 31, 2023 and 2022, capital assets are depreciated based on the following estimated useful life for each category: ​ ​ ​ Account Name Useful Life Machinery & Equipment ​ Five years Computer Equipment & Software ​ Three years Furniture & Fixtures ​ Five years ​ The Company regularly reviews whether facts and circumstances exist which indicate that the carrying amounts of capital assets, may not be recoverable or that the useful life of assets are shorter or longer than originally estimated. The Company assesses the recoverability of its assets by comparing the projected fair value of the related asset over the estimated remaining life against the respective carrying amounts. The Company considers factors such as estimated usage and expected lives of its capital assets in this analysis. Impairment, if any, is based on the excess of the carrying amount over the fair value of those assets. At December 31, 2023 and 2022, there were no impairment indicators. Impairment of Long-Lived Assets The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the asset’s carrying amount may not be recoverable. The Company conducts its long-lived asset impairment analyses in accordance with ASC 360-10-15, “Impairment or Disposal of Long-Lived Assets.” ASC 360-10-15 requires the Company to group assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and evaluate the asset group against the sum of the undiscounted future cash flows. If the undiscounted cash flows do not indicate the carrying amount of the asset is recoverable, an impairment charge is measured as the amount by which the carrying amount of the asset group exceeds its fair value based on discounted cash flow analysis or appraisals. Fair Value of Financial Instruments Fair value is defined as the exchange price that would be received for an asset or an exit price paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of the fair value hierarchy under Financial Accounting Standards Board (the “FASB”) Accounting Standards Codification (“ASC”) 820, Fair Value Measurement, are described as follows: Level 1 Level 2 Level 3 The financial instruments of the Company consist primarily of cash, U.S. government money market fund accounts, trade receivables, trade payables, short-term investments and debt securities. Because carrying values of cash, trade receivables and payables are equal to or approximate their fair value, the Company excluded these from the leveling requirements. U.S. government money market fund accounts are classified as Level 1 due to their short-term nature, their market interest rates and also based on the fact that they are publicly traded. The Company classifies short-term investments within Level 1 in the fair value hierarchy, because quoted prices for identical assets in active markets are used to determine fair value. The Company classifies the ‘On the Run’ Treasury bills within Level 1 and ‘Off the Run Treasury’ bills within Level 2 in the fair value hierarchy. The Company estimates the fair value of the investment in debt securities using Level 3 inputs. The Company also invested in non-convertible promissory note, prepayment for inventory and equity securities of two privately held companies, which were recorded on cost basis. See Notes 7 and 8 to the financial statements for more information. ​ Investment Valuation The Company’s investments in equity in privately held companies without readily determinable fair values, which are generally recorded at cost, plus or minus subsequent observable price changes in orderly transactions for identical or similar investments, less impairments. As part of its assessment for impairment indicators, the Company considers significant deterioration in the earnings performance and overall business prospects of the investee as well as significant adverse changes in the external environment these investments operate. If its qualitative assessment indicates the investments are impaired, the fair value of these equity securities would be estimated, which would involve a significant degree of judgment and subjectivity. The Company recorded an impairment of Deferred Revenue Deferred revenue represents amounts billed to or collected from customers for which the related revenues have not been recognized because one or more of the revenue recognition criteria have not been met. The full amount is expected to be recognized as revenues within one year from the balance sheet date and, therefore, such deferred amounts have been classified as current liabilities in the balance sheets presented. The Company generally invoices its clients in advance of a rental period with payment due upon receipt of the invoice. Revenue recognized for the year ended December 31, 2023 from amounts included in deferred revenue as of December 31, 2022 was $1,160. Revenue recognized for the year ended December 31, 2022 from amounts included in deferred revenue as of December 31, 2021 was $921. ​ Research and Development The Company expenses costs related to the research and development associated with the design, development, testing and enhancement of its products and services. Such expenses include salaries and related employee benefits, and fees paid to external service providers. The Company incurred Research and development expenses of $5,421 and $4,407 for the year ended December 31, 2023 and 2022, respectively. Stock-Based Compensation Stock-based compensation expense is measured based on the grant-date fair value of the stock-based awards. The Company recognizes stock-based compensation expense for the portion of each option grant or stock award that is expected to vest over the estimated period of service and vesting. The Company uses the Black-Scholes option pricing model as the method for determining the estimated grant-date fair value of stock options. The Black-Scholes option pricing model requires the use of subjective assumptions which determine the fair value of stock-based awards, including the option’s expected volatility. Forfeitures are recognized as incurred. Stock-based compensation expense is recognized on a straight-line basis over the requisite service period of the grant. See Note 15 to financial statements for the details. Employee Benefit Plan The Company has a savings plan that qualifies under Section 401(k) of the Internal Revenue Code of 1986, as amended (the “Code”). Effective January 1, 2022, the Company started to match 50% of employee’s 401(k) deferral up to a maximum of 6% of the employee’s eligible earnings. ​ Income Taxes The Company uses the asset and liability method to account for income taxes. Deferred tax assets and liabilities are recognized for the expected tax consequences attributable to the differences between financial reporting and the tax bases of existing assets and liabilities and net operating loss (“NOL”) carryforwards, and they are measured using enacted tax rates expected to be in effect when differences are expected to reverse. Recently Issued Accounting Pronouncements Accounting Pronouncements Recently Adopted In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments . Codification Improvements to Topic 326 Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments Financial Instruments – Credit Losses (Topic 326); have certain instruments within the scope of Subtopic 326-20 with an option to irrevocably elect the fair value option in Subtopic 825-10, applied on an instrument-by-instrument basis for eligible instruments upon adoption of Topic 326. This standard and related amendments are effective for the Company’s fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. The Company adopted this ASU prospectively effective January 1, 2023 and determined that the adoption of this new accounting standard did not have a material impact on its financial statements. In March 2020, FASB issued ASU No. 2020-03, Codification Improvements to Financial Instruments ​ In October 2021, the FASB issued ASU No. 2021-08, Business Combinations (Topic 805): ccounting for Contract Assets and Contract Liabilities from Contracts with Customers ​ In March 2022, the FASB issued ASU No. 2022-02, Financial Instruments-Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures,

Assets for Lease, net

Assets for Lease, net	12 Months Ended
	Dec. 31, 2023
Assets for Lease, net
Assets for Lease, net	3. Assets fo r The Company provides financing of certain equipment through operating leases (see Note 12 to the financial statements). Assets for lease consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2023 2022 Assets for lease ​ $ 3,375 ​ $ 3,702 Less: accumulated depreciation ​ (1,090) ​ (1,224) Assets for lease, net ​ $ 2,285 ​ $ 2,478 ​ Depreciation expense amounted to $307 and $386 for the years ended December 31, 2023 and 2022, respectively. Reduction to accumulated depreciation for returned items was $441 and $352 for the years ended December 31, 2023 and December 31, 2022, respectively. The Company recognized a loss on disposal of assets for lease in the amount of $369 and $463 for the years ended December 31, 2023 and 2022, respectively. As of December 31, 2023 and 2022, total assets for lease, net, in use at customer locations were $489 and $518, respectively.

Inventory

Inventory	12 Months Ended
	Dec. 31, 2023
Inventory
Inventory	4. Inventory As of December 31, 2023 and 2022, the inventory balance was $445 and $469 , respectively. Inventory includes finished goods of sensors, light blocking bags and heel warmers.

Property and Equipment, net

Property and Equipment, net	12 Months Ended
	Dec. 31, 2023
Property and Equipment, net
Property and Equipment, net	5. Property and Equipment, net Capital assets consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ ​ 2023 2022 Property and equipment, gross ​ $ 1,544 ​ $ 1,206 ​ Less: accumulated depreciation ​ (824) ​ (539) ​ Property and equipment, net ​ $ 720 ​ $ 667 ​ ​ Depreciation expense amounted to $292 and $203 for the years ended December 31, 2023 and 2022, respectively.

Long-Term Investments

Long-Term Investments	12 Months Ended
	Dec. 31, 2023
Long-Term Investments
Long-Term Investments	6. Long-Term Investments Carrying value of non-marketable securities is measured as the total initial cost plus the cumulative net gain (loss). Carrying value of non-marketable equity investments consist of the following for the periods presented: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ ​ 2023 2022 ​ Investments in SYNAPS Dx $ 512 ​ $ 512 ​ Investments in Mellitus Health, Inc. ​ ​ - ​ ​ 309 ​ Total long-term investments ​ $ 512 ​ $ 821 ​ ​ In September 2020, the Company acquired a promissory note from NeuroDiagnostics Inc., which is doing business as SYNAPS Dx, in the principal amount of $500. Subsequently, in December 2020, the Company agreed to convert the promissory note, together with all accrued interest thereon, into shares of preferred stock of SYNAPS Dx as repayment in full of the promissory note. The value of the note exchanged for the shares of preferred stock of SYNAPS Dx held by the Company as of December 31, 2023 and 2022 was approximately $512. In October 2020, the Company acquired from a seller a convertible promissory note previously issued by Mellitus to such seller for a purchase price of $59, which represented the $50 principal amount of the note and all accrued and unpaid interest thereon. Subsequently, in October 2020, the Company purchased $250 of shares of preferred stock of Mellitus, and in connection with such transaction, the convertible promissory note, together with all accrued interest thereon, also converted pursuant to its terms into shares of preferred stock of Mellitus as repayment in full of such convertible promissory note. The value of consideration exchanged for the shares of preferred stock of Mellitus held by the Company as of December 31, 2022 was approximately $309. The investments in SYNAPS Dx and Mellitus securities that were retained by the Company as of December 31, 2023 were recorded in accordance with ASC 321, Investments – equity securities, equity securities in privately-held companies without readily determinable fair values are generally recorded at cost, plus or minus subsequent observable price changes in orderly transactions for identical or similar investments, less impairments. The Company elected the practical expedient permitted by ASC 321 and recorded the above investments on a cost basis. As a part of the assessment for impairment indicators, the Company considers significant deterioration in the earnings performance and overall business prospects of the investee as well as significant adverse changes in the external environment these investments operate. If qualitative assessment indicates the investments are impaired, the fair value of these equity securities would be estimated, which would involve a significant degree of judgement and subjectivity. The Company assessed both investments for impairment in accordance with ASC 321. As of December 31, 2023, the Company determined that there was an impairment to the preferred stock investment in Mellitus and recorded an impairment of $309 due to the following factors: 1) due to continued operating losses; 2) due to lack of revenue growth; and 3) delayed capital raise. No impairment was recorded for the investments in SYNAPS Dx.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2023
Fair Value Measurements
Fair Value Measurements	7. Fair Value Measurements ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Hierarchy ​ Level 1 ​ Level 2 ​ Level 3 ​ Total As of December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Government money market fund accounts $ 41,373 ​ $ — ​ $ — ​ $ 41,373 (Included in cash and cash equivalents) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Treasury bills ​ — ​ ​ 10,494 ​ ​ — ​ ​ 10,494 (Included in short-term investments) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment in debt securities ​ — ​ ​ — ​ ​ 4,372 ​ ​ 4,372 (Included in notes held for investment) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Assets $ 41,373 ​ $ 10,494 ​ $ 4,372 ​ $ 56,239 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Level 1 ​ Level 2 ​ Level 3 ​ Total As of December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Treasury bill $ 20,073 ​ $ — ​ $ — ​ $ 20,073 (Included in short-term investments) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment in debt securities ​ — ​ ​ — ​ ​ 3,679 ​ ​ 3,679 (Included in notes held for investment) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Assets $ 20,073 ​ $ — ​ $ 3,679 ​ $ 23,752 ​ Treasury bill was purchased on October 10, 2023, at a cost of $10,414, and fair value accretes to maturity date at an interest rate of 5.35%. The treasury bill was classified as Level 2 as it is considered “off the run” because similar treasury bills were issued before the most recent issue and were outstanding as of December 31, 2023 and therefore not considered as liquid as other treasury bills with the same maturity date. As of December 31, 2023, the interest income recorded on these bills was $80. ​ The Company’s privately held debt securities were recorded at fair value on a recurring basis. The estimation of fair value for these investments requires the use of significant unobservable inputs, and as a result, the Company deems these assets as Level 3 within the fair value measurement framework. ​ The Company valued the debt securities using a bond plus call option model reflecting the cash flow from the debt securities and assuming a 5% probability of an equity financing, a 75% probability of a change of control, and a 20% probability of payment at maturity or an insolvency event. The fair value of the Company’s privately held debt securities were estimated at $4,372 and $3,679 as of December 31, 2023 and December 31, 2022, respectively. ​ The key inputs for the valuation model are: ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2023 ​ Risk-free rate ​ 3.94% - 5.26% ​ Cash flow discount rate ​ 27.8% ​ Expert term in years ​ 0.25- 2.92 ​ Expected volatility ​ 120% ​ ​ The following table represents changes in the notes held for the investments with significant unobservable inputs (Level 3): ​ ​ ​ ​ ​ ​ ​ ​ Convertible Notes ​ Balance as of December 31, 2022 ​ $ 3,679 ​ Purchased ​ ​ 1,000 ​ Change in fair value of the notes held for investment ​ ​ (307) ​ Balance as of December 31, 2023 ​ $ 4,372 ​ ​

Notes held for investment

Notes held for investment	12 Months Ended
	Dec. 31, 2023
Notes held for investment
Notes held for investment	8. Notes held for investment Notes receivable consist of the following for the periods presented: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ December 31, ​ ​ ​ 2023 ​ ​ 2022 ​ Senior secured promissory notes ​ $ 1,000 ​ $ 1,000 ​ Secured convertible promissory notes ​ ​ 4,372 ​ ​ 3,679 ​ Total notes held for investment ​ $ 5,372 ​ $ 4,679 ​ ​ In June 2022, the Company loaned Mellitus an aggregate of $1,000 through the purchase of two senior secured promissory notes that bear interest at a rate of 5% per annum, and mature in three years unless accelerated due to an event of default as provided in the notes. Repayment of notes is secured by a first priority interest in all of Mellitus’ assets. In May 2022, to facilitate the subordination of such notes in connection with the purchase of the senior secured notes, the Company acquired $179 aggregate principal amount of outstanding convertible notes of Mellitus, which, as amended, mature July 5, 2025, if not automatically converted into preferred stock prior thereto. This note bears an interest rate of 10% per annum. ​ In December 2022, the Company entered into a senior convertible promissory note (also referred as debt security) arrangement with Monarch, providing Monarch with up to $5,000 in available funding, of which $4,500 , in principal was drawn as of December 31, 2023. The remaining $500 is available to be drawn at any time unless there is an event of default (as defined in the note) that is continuing. The Monarch debt security accrues interest at 10% per annum, payable monthly, and the principal balance is due December 6, 2024. The note along with up to $100 of transaction expenses is due and payable on the occurrence of an event of default or change of control unless accelerated due to the conversion into preferred stock prior thereto at the option of the Company. The Company has the option to extend the maturity date for two consecutive one-year terms. The Monarch debt security can be converted into Monarch’s shares at the Company’s option upon (a) an equity financing at Monarch, (b) upon a change of control at Monarch, or (c) at the Company’s option at any time prior to the maturity date. If converted upon a change of control, the Company has the right to receive a cash payment equal to the balance of the Monarch debt security or the amount payable upon conversion into Monarch’s shares. The Monarch debt security is redeemable at any time at Monarch’s option or automatically upon an event of default (as defined in the note) . ​ Financial Instruments s of December 31, 2022, the Company estimated the fair value of the Monarch debt security to be $3,500 and the Mellitus secured convertible promissory note to be $179 , which were equivalent of the outstanding principal balances on December 31, 2022. ​ The Company recognizes interest income on the Monarch and Mellitus debt securities, which is included in interest and dividend income in the statements of income. Accrued interest on Monarch convertible promissory note and Mellitus senior secured promissory note was included in prepaid and other current assets. For the year ended December 31, 2023 and 2022, the Company recognized $449 and $20 , respectively, of interest income from Monarch and Mellitus debt securities. The Company recognizes changes in fair value of the notes in the statements of income separately from the interest income. For the year ended December 31, 2023, the Company recorded change in fair value of $128 for the Monarch debt security and $179 for Mellitus secured convertible note. For the year ended December 31, 2022, the Company recorded no change in fair value

Other Non-current assets

Other Non-current assets	12 Months Ended
	Dec. 31, 2023
Other Non-current assets
Other Non-current assets	9. Other non-current assets ​ Other non-current assets consist of the following for the periods presented: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ ​ 2023 2022 Prepaid licenses ​ ​ $ — ​ $ 2,490 Other ​ ​ ​ 270 ​ ​ 352 Total other non-current assets ​ ​ $ 270 ​ $ 2,842 ​ In April 2021, the Company entered into a five-year agreement, as amended in December 2022, with Mellitus to exclusively market and distribute its product line in the United States, including Puerto Rico, except for selected accounts. Under this distribution agreement and its amendments, the Company agreed to purchase $2,500 of product licenses and prepaid $2,500 for the license purchases. Revenue from these product licenses is recognized in accordance with ASC 606, Revenue from Contracts with Customers . The Company did not generate significant revenue from these product licenses during the year ended December 31, 2023 and 2022. In the fourth quarter, the Company assessed the recoverability of prepayment before the contract period and wrote-off the balance of $2,476 as of December 31, 2023, which was included in cost of revenues in the statement of income. The Company determined that the prepaid licenses would not likely be recovered by the end of the license period based on the quantitative and qualitative factors such as lack of meaningful revenue generated to date and a delayed uptake by potential customers in the fourth quarter of 2023. Other includes right-of-use asset (“ROU”) of $150 , miscellaneous receivables of $100 and long-term deposits of $20 as of December 31, 2023. As of December 31, 2022, ROU asset of $233 and miscellaneous receivable of $100 and long term deposits balances of $19 , respectively.

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2023
Accrued Expenses
Accrued Expenses	10. Accrued Expenses Accrued expenses consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2023 2022 Compensation ​ $ 2,008 ​ $ 2,467 Accrued Taxes ​ ​ 1,991 ​ ​ 1,923 Miscellaneous Accruals ​ 503 ​ 358 Total Accrued Expenses ​ $ 4,502 ​ $ 4,748 ​

Concentration of Credit Risk

Concentration of Credit Risk	12 Months Ended
	Dec. 31, 2023
Concentration of Credit Risk
Concentration of Credit Risk	11. Concentration of Credit Risk Credit risk is the risk of loss from amounts owed by the financial counterparties. Credit risk can occur at multiple levels; as a result of broad economic conditions, challenges within specific sectors of the economy, or from issues affecting individual companies. Financial instruments that potentially subject the Company to credit risk consist of cash and accounts receivable. The Company maintains cash with major financial institutions. The Company’s cash consists of bank deposits held with banks that, at times, exceed federally insured limits. The cash and cash equivalents also include short term treasury bills with original maturities of three months or less and U.S. government money market fund accounts. As of December 31,2023, the Company held deposits of $5,465 , which exceeded federal deposit corporation limits. The Company also invested in U.S. treasury bills in the amount of $10,494 and U.S. government money market accounts of $41,373 Management periodically monitors the creditworthiness of its customers and believes that it has adequately provided for any exposure to potential credit loss. For the year ended December 31, 2023, two customers accounted for 36.0% and 34.9% of the Company’s revenue. For the year ended December 31, 2022, two customers accounted for 40.4%, and 29.0% of the Company’s revenue. As of December 31, 2023, three customers accounted for 27.5%, 27.5% and 23.6% of the Company’s accounts receivable. As of December 31, 2022, three customers accounted for 26.8%, 25.9% and 16.8% of the Company’s accounts receivable. As of December 31, 2023 and 2022 the allowance for doubtful accounts was $287 and $109, respectively. As of December 31, 2023, two vendors accounted for 24.0% and $10.1% of the Company’s accounts payable. As of December 31, 2022, two vendor accounted for 25.8% and 10.8% of the Company’s accounts payable.

Leases

Leases	12 Months Ended
	Dec. 31, 2023
Lessee Arrangements
Lessee Arrangements	12. Leases Lessee Arrangements On July 31, 2020, the Company entered into a 61-month lease agreement for office space to use, as necessary, for office administration, lab space and assembly and storage purposes, located in Santa Clara, California. The Company took possession of the leased office space in September 2020, and the lease is effective through September 30, 2025. The discount rate determined for this lease was 2.5%. As of December 31, 2023, the remaining lease term is one year and nine months with no options to renew. The Company recognized facilities lease expenses of $88 and $88 for the years ended December 31, 2023 and 2022, respectively. The following table summarizes the future minimum rental payments required under operating leases that had initial or remaining non-cancelable lease terms greater than one year as of December 31, 2023: ​ ​ ​ ​ ​ ​ Total 2024 ​ 93 2025 ​ 71 Total undiscounted future minimum lease payments ​ 164 Less: present value discount ​ (4) Total lease liabilities ​ 160 Lease expense in excess cash payment ​ (10) Total ROU asset ​ $ 150 ​ As of December 31, 2023, the Company’s ROU asset current noncurrent Lessor Arrangements The Company enters into contracts with customers for the Company’s QuantaFlo ® Variable-fee Revenue The Company recognizes revenues from variable-fee licenses (e.g., fee per test) and sales of hardware equipment and accessories in accordance with Topic 606. Total revenues from variable-fee licenses were approximately $28,992 and $21,277 for the years ended December 31, 2023 and 2022, respectively. Total revenues from sales of hardware and equipment accessories were approximately $1,930 and $1,358 for the years ended December 31, 2023 and 2022, respectively.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies
Commitments and Contingencies	13. Commitments and Contingencies Senior Secured Convertible Note In December 2022, the Company committed a loan of $5,000 to Monarch through the purchase of a senior secured convertible promissory note that bears interest at a rate of 10% per annum and matures on the second anniversary from the issue date, which can be extended for up to two additional consecutive one-year terms in the Company’s sole discretion. The note along with up to $100 of transaction expenses is due and payable on the occurrence of an event of default or change of control unless accelerated due to the conversion into preferred stock prior thereto at the option of the Company. Monarch borrowed $4,500 out of the committed amount of $5,000 as of December 31, 2023. Repayment of the note is secured by a first priority interest in all of Monarchs’ assets. See Note 8 to financial statements. Indemnification Obligations The Company enters into agreements with customers, partners, lenders, consultants, lessors, contractors, sales representatives and parties to certain transactions in the ordinary course of the Company’s business. These agreements may require the Company to indemnify the other party against third party claims alleging that its product infringes a patent or copyright. Certain of these agreements require the Company to indemnify the other party against losses arising from: a breach of representations or covenants, claims relating to property damage, personal injury or acts or omissions of the Company, its employees, agents or representatives. The Company has also agreed to indemnify the directors and certain of the officers and employees in accordance with the by-laws of the Company. These indemnification provisions will vary based upon the nature and terms of the agreements. In many cases, these indemnification provisions do not contain limits on the Company’s liability, and the occurrence of contingent events that will trigger payment under these indemnities is difficult to predict. As a result, the Company cannot estimate its potential liability under these indemnities. The Company believes that the likelihood of conditions arising that would trigger these indemnities is remote and, historically, the Company had not made any significant payment under such indemnification provisions. Accordingly, the Company has not recorded any liabilities relating to these agreements. In certain cases, the Company has recourse against third parties with respect to the aforesaid indemnities, and the Company believes it maintains adequate levels of insurance coverage to protect the Company with respect to potential claims arising from such agreements. ​ Other ​ The Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) provides for an employee retention payroll tax credit for certain employers, which is a refundable tax credit against certain employment taxes equal to 50% of the qualified wages an eligible employer pays to employees after March 12, 2020 and before December 31, 2021. For each employee, wages (including health plan costs) up to $10,000 can be counted to determine the amount of the 50% credit. The Company started claiming this credit on its July 2020 payroll until mid-April 2021 when it determined that it no longer qualified given the change in government restrictions on travel that had impacted its sales activities. The Company’s determination that it qualified to claim the employee retention payroll tax credit is subjective and subject to audit by the Internal Revenue Service (“IRS”). If the IRS were to disagree with the Company’s tax position, it could be required to pay the retention credit claimed, along with penalties. As of December 31, 2021, the Company claimed $1.24 million in this retention credit. No credit was claimed for the year ended December 31, 2022 and December 31, 2023. Legal Matter From time to time, the Company may be subject to legal proceedings and claims in the ordinary course of business. The Company is not currently a party to any litigation the outcome of which, if determined adversely to it, would individually or in the aggregate be reasonably expected to have a material adverse effect on its business, operating results, cash flows or financial condition.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity
Stockholders' Equity	14. Stockholders’ Equity The Company has 50,000,000 authorized shares of capital stock, all of which are designated as common stock with par value of $0.001 per share. Each holder of shares of common stock is entitled to one vote for each share held. Treasury Stock Acquired On March 14, 2022, the Company’s Board of Directors authorized a share repurchase program under which it may repurchase up to $20.0 million of its outstanding common stock. Under this program the Company may purchase shares on a discretionary basis from time to time through open market purchases, privately negotiated transactions or other means, including through Rule 10b5-1 trading plans or through the use of other techniques such as accelerated share repurchases. The timing and amount of any transactions will be subject to the discretion of the Company based upon market conditions and other opportunities that it may have for the use or investment of its cash balances. The repurchase program has no expiration date, does not require the purchase of any minimum number of shares and may be suspended, modified or discontinued at any time without prior notice. The Company purchased 148,500 shares at a cost of approximately $4,991 during the year ended December 31, 2022. No purchases were made during the year ended December 31, 2023. For the years ended December 31, 2023 and 2022, a total of 1,813,175 and 1,548,545 shares of common stock, respectively, were reserved for issuance upon the exercise of outstanding stock options, as follows: ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ 2023 2022 Common stock warrants ​ — 76,875 Stock options ​ 1,813,175 1,471,670 Total ​ 1,813,175 1,548,545 ​ Warrants acquired- related party transaction ​ On May 17, 2023, the Company repurchased outstanding warrants to acquire 76,875 shares of common stock from its chief executive officer at a cost of $1,949. The warrants, which were originally issued on June 7, 2012 (16,875 shares) with an exercise price of $4.00 per share and on July 31, 2013 (60,000 shares), with an exercise price of $4.50 per share, were amended in September 2015 and, as amended, had an expiration date of July 31, 2023. The $1,949 aggregate cash purchase price reflects the difference between the aggregate exercise price of the warrants and the aggregate fair market value of the shares of common stock underlying the warrants, based on the closing price of a share of the Company’s common stock on May 16, 2023, the date of the warrant repurchase agreement. Following the warrant repurchase, the warrants were cancelled and are no longer issued and outstanding.

Stock Option Plan

Stock Option Plan	12 Months Ended
	Dec. 31, 2023
Stock Option Plan
Stock Option Plan	15. Stock Option Plan The Company’s stock-based compensation program is designed to attract and retain employees while also aligning employees’ interests with the interests of its stockholders. Stock options have been granted to employees under the stockholder-approved 2007 Key Person Stock Option Plan (“2007 Plan”) or the stockholder-approved 2014 Stock Incentive Plan (“2014 Plan”). Stockholder approval of the 2014 Plan became effective in September 2014. The 2014 Plan originally provided that the aggregate number of shares of common stock that may be issued pursuant to awards granted under the 2014 Plan may not exceed 450,000 shares (the “Share Reserve”), however in October 2015, the stockholders approved a 1,500,000 increase to the Share Reserve. In addition, the Share Reserve automatically increases on January 1st of each year, for a period of not more than 10 years, beginning on January 1st of the year following the year in which the 2014 Plan became effective and ending on (and including) January 1, 2024, in an amount equal to 4% of the total number of shares of common stock outstanding on December 31st of the preceding calendar year. The Company’s board of directors may act prior to January 1st of a given year to provide that there will be no January 1st increase in the Share Reserve for such year or that the increase in the Share Reserve for such year will be a lesser number of shares of common stock than would otherwise occur. The Share Reserve is currently 3,582,888 shares as of December 31, 2023. In light of stockholder approval of the 2014 Plan, the Company no longer grants equity awards under the 2007 Plan. As of December 31, 2023, there were no shares available for future stock-based compensation grants under the 2007 Plan and 1,813,175 shares of an aggregate total of 3,582,888 shares available for future stock-based compensation grants under the 2014 Plan. Aggregate intrinsic value represents the difference between the closing market value as of December 31, 2023 of the underlying common stock and the exercise price of outstanding, in-the-money options. A summary of the Company’s stock option activity and related information for 2023 and 2022 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Number of ​ Weighted ​ Remaining ​ Aggregate ​ ​ Stock Options ​ Average ​ Contractual ​ Intrinsic Value ​ Outstanding Exercise Price Term (In Years) (In Thousands) Balance, December 31, 2022 1,287,847 ​ $ 3.44 3.03 ​ $ 38,053 Options exercised (283,562) ​ ​ 3.36 ​ — ​ ​ — Options granted ​ 17,950 ​ ​ 25.52 ​ 9.53 ​ ​ — Options cancelled ​ (450) ​ ​ — ​ — ​ ​ — Balance, December 31, 2023 1,021,785 ​ $ 3.84 ​ 3.76 ​ $ 41,333 Exercisable as of December 31, 2023 1,001,344 ​ $ 3.38 ​ 2.10 ​ $ 40,964 ​ As of December 31, 2023, the fair value of unvested stock options was approximately $382. This unrecognized stock-based compensation expense is expected to be recorded over a weighted average period of 3.76 years. During the year ended December 31, 2023 , the Company awarded stock options of 17,500 net of cancellations to employees as compensation pursuant to the 2014 Plan. Of these options, 1/4 1/48 The fair value of each option grant is estimated using the Black-Scholes option pricing model. The weighted-average assumptions used, and the calculated weighted average fair values of options are as follows: ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2023 2022 ​ Expected term (in years) ​ 7 ​ 7 ​ Risk-free interest rate ​ 4.14-4.41 ​ 2.88 ​ Expected volatility ​ 69.0%-79.5% ​ 78.6% ​ Expected dividend rate ​ 0 ​ 0 ​ Fair value of options granted ​ $17.54-$19.04 ​ $22.27 ​ ​ Stock grants The Company granted 18,048 and 9,421 shares of fully vested stock to employees and board of directors in the year ended December 31, 2023 and 2022, respectively. Grant date fair value of the stock was $860 and $723 for the year ended December 31, 2023 and 2022, respectively. The Company has recorded an expense of $944 and $741 as it relates to stock-based compensation for the years ended December 31, 2023 and 2022, respectively, which was allocated as follows based on the role and responsibility of the recipient in the Company: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31 ​ ​ December 31 ​ ​ 2023 2022 Cost of Revenues ​ ​ ​ $ 8 ​ $ — Engineering and Product Development ​ ​ ​ ​ 53 ​ ​ 45 Sales and Marketing ​ ​ ​ 317 ​ 173 General and Administrative ​ ​ ​ 566 ​ 523 Total ​ ​ ​ $ 944 ​ $ 741 ​

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Taxes
Income Taxes	16. Income Taxes The components of the provision for income taxes are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 Current tax provision: ​ ​ Federal ​ $ 3,576 $ 3,201 State ​ 605 517 Total current tax provision ​ ​ 4,181 ​ ​ 3,718 Deferred tax provision: ​ ​ ​ Federal ​ (680) (373) State ​ 16 22 Total deferred tax provision ​ ​ (664) ​ ​ (351) Total income tax provision ​ $ 3,517 $ 3,367 ​ A summary of the differences between the Company’s effective income tax rate and the federal statutory income tax rate for the years ended December 31, 2023 and 2022 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 ​ Federal statutory rate 21.00 % 21.00 % State income tax rate, net of federal benefit 2.04 % 2.57 % Stock-based compensation ​ (7.98) % (4.03) % Permanent items (0.71) % (0.93) % Other 0.24 % 0.35 % Effective income tax rate 14.59 % 18.96 % ​ Deferred tax assets are comprised of the following at December 31: ​ ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 Net operating loss carryforwards $ 188 $ 303 Deferred revenue ​ 268 ​ 278 Stock based compensation ​ 385 ​ 529 Accrual and reserves ​ 251 ​ 297 Research and development credits ​ 262 ​ 254 Other ​ ​ 156 ​ ​ 2 Depreciation and amortization ​ ​ 1,450 ​ ​ 633 Lease liability ​ ​ 38 ​ ​ 59 Total gross deferred tax assets ​ 2,998 ​ 2,355 Less valuation allowance ​ — ​ — Net deferred tax assets ​ ​ 2,998 ​ ​ 2,355 Deferred tax liabilities: ​ ​ ​ ​ ​ ​ Right of use assets ​ ​ (36) ​ ​ (56) Total deferred tax liabilities ​ ​ (36) ​ ​ (56) Net deferred tax assets ​ $ 2,962 $ 2,299 ​ Federal and California tax laws imposes significant restrictions on the utilization of net operating loss (“NOL”) carryforwards in the event of a change in ownership of the Company, as defined by Section 382 of the Code (“Section 382”). The Company completed a formal 382 study for the period from January 1, 2012 through June 30, 2019 and concluded that a change in ownership has likely occurred. The Company has no NOL carryforwards for Federal income tax purposes and approximately $2,607 for California income tax purposes as of December 31, 2023. The state NOL carryforwards, if not utilized, will expire beginning in 2035 and extended to 2038. As of December 31, 2023 and 2022, the Company had $470 and $401, respectively, of unrecognized tax benefits (excluding interest and penalties) that, if recognized, would affect the effective tax rate. The following table summarizes the activity related to the Company’s gross unrecognized tax benefits: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Unrecognized Tax Benefits 2023 ​ Gross Unrecognized Tax Benefits 2022 Unrecognized tax benefits – January 1 ​ $ 401 $ 476 Gross increases related to prior tax positions ​ 4 — Gross decreases related to prior tax positions ​ ​ — ​ ​ (120) Gross increases related to current tax positions ​ 65 45 Unrecognized tax benefits – December 31 ​ $ 470 $ 401 ​ The Company’s policy is to recognize interest and penalty expenses related to uncertain tax positions in income tax expense, which was $87 and $30 for the years ended December 31, 2023 and 2022, respectively. The Company files income tax returns in the U.S. federal and various state tax jurisdictions. The Company’s tax years beginning in 2019 remain open for examination by the state tax authorities for four years. The Company’s tax years beginning in 2020 remain open for examination by the federal tax authorities for three years. Tax years beginning in 2016 will remain open for examination from the date of utilization of any NOL or credits. The Company does not have any tax positions for which it is reasonably possible the total amount of gross unrecognized tax benefits will increase or decrease within 12 months of the year-ended December 31, 2023. ​ Before January 1, 2022, IRC §174 provided a taxpayer may treat research or experimental expenditures which are paid or incurred by the taxpayer during the taxable year in connection with the taxpayer’s trade or business as expenses. As amended by TCJA, IRC §174 provides that in a case of a taxpayer's specified research or experimental expenditures for any taxable year beginning after December 31, 2021, no deduction is allowed for such expenditures. The expenditures must be charged to capital account and is allowed an amortization deduction of such expenditures ratably over the 5-year period (15-year period in the case of any specified research expenditures which are attributable to foreign research). The Company capitalized ​ On August 16, 2022, the CHIPS and Science Act of 2022 or Creating Helpful Incentives to Produce Semiconductors for America Act, and Inflation Reduction Act (IRA Act) was signed into law in the United States. Among other things, CHIPS and Science Act provides incentives and tax credits for the global chip manufacturers who choose to set-up or expand existing operations in the United States. The IRA Act imposes a 15% corporate alternative minimum tax for tax years beginning after December 31, 2022, levies a 1% excise tax on net stock repurchases after December 31, 2022, and provides tax incentives to promote clean energy. This act is primarily applicable to large corporations with an annual revenue of $1 billion or over. Implementation of this act has no impact on the Company’s financial statements as of December 31, 2023.

Net Income Per Share, Basic and

Net Income Per Share, Basic and Diluted	12 Months Ended
	Dec. 31, 2023
Net Income Per Share, Basic and Diluted
Net Income Per Share, Basic and Diluted	17. Net Income Per Share, Basic and Diluted Basic earnings per share (“EPS”) represent net income attributable to common shareholders divided by the weighted average number of common shares outstanding during the measurement period. Diluted EPS represents net income attributable to common shareholders divided by the weighted average number of common shares outstanding during the measurement period while also giving effect to all potentially dilutive common shares that were outstanding during the period using the treasury stock method. Basic and diluted net EPS is calculated as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ ​ 2023 ​ 2022 ​ ​ Shares Net Income EPS Shares Net Income EPS Basic EPS ​ 6,732,806 ​ $ 20,583 ​ $ 3.06 6,726,687 ​ $ 14,325 ​ $ 2.13 Common stock warrants ​ — ​ — ​ — 68,588 ​ — ​ — Common stock options ​ 1,086,353 ​ — ​ — 1,204,475 ​ — ​ — Diluted EPS ​ 7,819,159 ​ $ 20,583 ​ $ 2.63 7,999,750 ​ $ 14,325 ​ $ 1.79 ​

Strategic Plan to Streamline Op

Strategic Plan to Streamline Operations	12 Months Ended
	Dec. 31, 2023
Strategic Plan to Streamline Operations
Strategic Plan to Streamline Operations	​ ​ ​ ​ ​ ​ ​ ​ 18. Strategic Plan to Streamline Operations ​ On July 11, 2023, the Company’s board of directors, approved a strategic plan to streamline operations and reduce employee headcount by approximately 30% by September 15, 2023. This plan was meant to be proactive and seeks to drive operational efficiency, while still allowing the Company to provide high quality service to its customers. As of December 31, 2023, the Company accrued and paid ​

Summary of Significant Accoun_2

Summary of Significant Accounting Policies and Estimates (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies Abstract
Basis of Presentation	Basis for Presentation The Company’s financial statements and accompanying notes are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”).
Use of Estimates	Use of Estimates The preparation of the accompanying financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities at the date of the financial statements, and reported amounts of revenues and expenses, and related disclosures during the reporting period. Significant items subject to such estimates include allowance for credit losses, valuation of equipment on lease, recognition and measurement of current and deferred income taxes, valuation and recognition of investments and valuation of inventory. These estimates and assumptions are based on management’s best estimates and judgment. Management regularly evaluates its estimates and assumptions using historical experience and other factors; however, actual results could differ significantly from these estimates.
Concentration of Credit Risk	Concentration of Credit Risk ​ Financial instruments that potentially subject the Company to concentrations of credit risk primarily consist of cash, cash equivalents, restricted cash, accounts receivable and trade payables. The Company maintains its cash with major financial institutions. The Company’s cash consists of bank deposits held with banks that, at times, exceed federally insured limits. The cash and cash equivalents also include short term treasury bills with original maturities of three months or less and U.S. government money market fund accounts. The Company manages its accounts receivable credit risk through ongoing credit evaluation of its customers’ financial conditions. The Company generally does not require collateral from its customers. For information regarding the Company’s significant customers and vendors, see Note 11 to financial statements.
Revenue Recognition	Revenue Recognition The Company generates revenues primarily from the rental or license of its vascular testing product. The Company recognizes revenues from the licensing of its product primarily pursuant to agreements that automatically renew each month with revenue recognized on a daily convention basis or when the test is performed. The Company’s arrangements with customers for its vascular testing product are normally on a month-to-month basis with fees billed at the rates established in the customer agreement, either on a fixed or variable (e.g. fee per test) basis, as earned. The Company also recognizes revenue for hardware and supplies sales as of the date of shipment. Shipping and handling costs are included in cost of revenues in the statement of income.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents are comprised of highly liquid investments purchased with an initial maturity date of three months or less. Funds held as investments in money market funds are included within cash and cash equivalents.
Short-Term Investments	Short-Term Investments Short-term investments are those that can be readily converted into cash and also any investment instruments that will mature within one year or which are expected to be liquidated within one year.
Accounts Receivable and Allowance for Credit Losses	Accounts Receivable and Allowance for Credit Losses Accounts receivables are recorded at the invoiced amount, net of allowances for credit losses. T he allowance for credit losses is based on management’s assessment of the collectability of accounts. The Company regularly reviews the adequacy of this allowance for credit losses by considering historical experience, the age of the accounts receivable balances, the credit quality of the customers, current economic conditions, reasonable and supportable forecasts of future economic conditions, and other factors that may affect customers’ ability to pay to determine whether a specific reserve is appropriate. Accounts receivable deemed uncollectable are charged against the allowance for credit losses when identified. ​ As of December 31, 2023, the allowance for credit losses was $287. Net change due to credit losses during the year was $178. Allowance balance as of December 31, 2022, was $109.
Inventory	Inventory Inventory, which is made up of finished goods, is recorded at the lower of cost or net realizable value. Cost is determined on the first-in, first-out method. The Company periodically analyzes its inventory levels to identify inventory that has a cost basis in excess of its estimated realizable value, and writes down such inventory as appropriate.
Assets for Lease	Assets for Lease Assets for lease are recorded at cost. At December 31, 2023 and 2022, assets for lease consisted of vascular testing devices, which are primarily leased to customers. The cost of such assets for lease is depreciated on a straight-line basis over 36 months for the units outstanding and recorded as cost of revenues. The Company regularly reviews whether facts and circumstances exist which indicate that the carrying amounts of assets, may not be recoverable or that the useful life of assets are shorter or longer than originally estimated. The Company assesses the recoverability of its assets by comparing the projected undiscounted net cash flows associated with the related assets over their estimated remaining lives against their respective carrying amounts. The Company considers factors such as estimated usage and expected lives of its assets for lease in this analysis. Impairment, if any, is based on the excess of the carrying amount over the fair value of those assets. At December 31, 2023 and 2022, there were no impairment indicators.
Property and Equipment	Property and Equipment Capital assets are recorded at cost. The cost of such capital assets is depreciated on a straight-line basis over a term depending on the assigned category (described below) and recorded as depreciation for capital assets recorded in engineering and product development, sales and marketing and general and administrative expenses. At December 31, 2023 and 2022, capital assets are classified into one of the following categories: ​ ​ ​ Category Name Description Machinery & Equipment ​ Manufacturing, R&D, or other non-office equipment Computer Equipment & Software ​ Software, computers, monitors, printers and other related equipment. Furniture & Fixtures ​ Office equipment and furniture owned by the company ​ At December 31, 2023 and 2022, capital assets are depreciated based on the following estimated useful life for each category: ​ ​ ​ Account Name Useful Life Machinery & Equipment ​ Five years Computer Equipment & Software ​ Three years Furniture & Fixtures ​ Five years ​ The Company regularly reviews whether facts and circumstances exist which indicate that the carrying amounts of capital assets, may not be recoverable or that the useful life of assets are shorter or longer than originally estimated. The Company assesses the recoverability of its assets by comparing the projected fair value of the related asset over the estimated remaining life against the respective carrying amounts. The Company considers factors such as estimated usage and expected lives of its capital assets in this analysis. Impairment, if any, is based on the excess of the carrying amount over the fair value of those assets. At December 31, 2023 and 2022, there were no impairment indicators.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the asset’s carrying amount may not be recoverable. The Company conducts its long-lived asset impairment analyses in accordance with ASC 360-10-15, “Impairment or Disposal of Long-Lived Assets.” ASC 360-10-15 requires the Company to group assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and evaluate the asset group against the sum of the undiscounted future cash flows. If the undiscounted cash flows do not indicate the carrying amount of the asset is recoverable, an impairment charge is measured as the amount by which the carrying amount of the asset group exceeds its fair value based on discounted cash flow analysis or appraisals.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Fair value is defined as the exchange price that would be received for an asset or an exit price paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of the fair value hierarchy under Financial Accounting Standards Board (the “FASB”) Accounting Standards Codification (“ASC”) 820, Fair Value Measurement, are described as follows: Level 1 Level 2 Level 3 The financial instruments of the Company consist primarily of cash, U.S. government money market fund accounts, trade receivables, trade payables, short-term investments and debt securities. Because carrying values of cash, trade receivables and payables are equal to or approximate their fair value, the Company excluded these from the leveling requirements. U.S. government money market fund accounts are classified as Level 1 due to their short-term nature, their market interest rates and also based on the fact that they are publicly traded. The Company classifies short-term investments within Level 1 in the fair value hierarchy, because quoted prices for identical assets in active markets are used to determine fair value. The Company classifies the ‘On the Run’ Treasury bills within Level 1 and ‘Off the Run Treasury’ bills within Level 2 in the fair value hierarchy. The Company estimates the fair value of the investment in debt securities using Level 3 inputs. The Company also invested in non-convertible promissory note, prepayment for inventory and equity securities of two privately held companies, which were recorded on cost basis. See Notes 7 and 8 to the financial statements for more information.
Investment Valuation	Investment Valuation The Company’s investments in equity in privately held companies without readily determinable fair values, which are generally recorded at cost, plus or minus subsequent observable price changes in orderly transactions for identical or similar investments, less impairments. As part of its assessment for impairment indicators, the Company considers significant deterioration in the earnings performance and overall business prospects of the investee as well as significant adverse changes in the external environment these investments operate. If its qualitative assessment indicates the investments are impaired, the fair value of these equity securities would be estimated, which would involve a significant degree of judgment and subjectivity. The Company recorded an impairment of
Deferred Revenue	Deferred Revenue Deferred revenue represents amounts billed to or collected from customers for which the related revenues have not been recognized because one or more of the revenue recognition criteria have not been met. The full amount is expected to be recognized as revenues within one year from the balance sheet date and, therefore, such deferred amounts have been classified as current liabilities in the balance sheets presented. The Company generally invoices its clients in advance of a rental period with payment due upon receipt of the invoice. Revenue recognized for the year ended December 31, 2023 from amounts included in deferred revenue as of December 31, 2022 was $1,160. Revenue recognized for the year ended December 31, 2022 from amounts included in deferred revenue as of December 31, 2021 was $921. ​
Research and Development	Research and Development The Company expenses costs related to the research and development associated with the design, development, testing and enhancement of its products and services. Such expenses include salaries and related employee benefits, and fees paid to external service providers. The Company incurred Research and development expenses of $5,421 and $4,407 for the year ended December 31, 2023 and 2022, respectively.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation expense is measured based on the grant-date fair value of the stock-based awards. The Company recognizes stock-based compensation expense for the portion of each option grant or stock award that is expected to vest over the estimated period of service and vesting. The Company uses the Black-Scholes option pricing model as the method for determining the estimated grant-date fair value of stock options. The Black-Scholes option pricing model requires the use of subjective assumptions which determine the fair value of stock-based awards, including the option’s expected volatility. Forfeitures are recognized as incurred. Stock-based compensation expense is recognized on a straight-line basis over the requisite service period of the grant. See Note 15 to financial statements for the details.
Employee Benefit Plan	Employee Benefit Plan The Company has a savings plan that qualifies under Section 401(k) of the Internal Revenue Code of 1986, as amended (the “Code”). Effective January 1, 2022, the Company started to match 50% of employee’s 401(k) deferral up to a maximum of 6% of the employee’s eligible earnings.
Income Taxes	Income Taxes The Company uses the asset and liability method to account for income taxes. Deferred tax assets and liabilities are recognized for the expected tax consequences attributable to the differences between financial reporting and the tax bases of existing assets and liabilities and net operating loss (“NOL”) carryforwards, and they are measured using enacted tax rates expected to be in effect when differences are expected to reverse.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Accounting Pronouncements Recently Adopted In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments . Codification Improvements to Topic 326 Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments Financial Instruments – Credit Losses (Topic 326); have certain instruments within the scope of Subtopic 326-20 with an option to irrevocably elect the fair value option in Subtopic 825-10, applied on an instrument-by-instrument basis for eligible instruments upon adoption of Topic 326. This standard and related amendments are effective for the Company’s fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. The Company adopted this ASU prospectively effective January 1, 2023 and determined that the adoption of this new accounting standard did not have a material impact on its financial statements. In March 2020, FASB issued ASU No. 2020-03, Codification Improvements to Financial Instruments ​ In October 2021, the FASB issued ASU No. 2021-08, Business Combinations (Topic 805): ccounting for Contract Assets and Contract Liabilities from Contracts with Customers ​ In March 2022, the FASB issued ASU No. 2022-02, Financial Instruments-Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures,

Summary of Significant Accoun_3

Summary of Significant Accounting Policies and Estimates (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies Abstract
Schedule of estimated useful lives of property and equipment	At December 31, 2023 and 2022, capital assets are depreciated based on the following estimated useful life for each category: ​ ​ ​ Account Name Useful Life Machinery & Equipment ​ Five years Computer Equipment & Software ​ Three years Furniture & Fixtures ​ Five years

Assets for Lease, net (Tables)

Assets for Lease, net (Tables)	12 Months Ended
	Dec. 31, 2023
Assets for Lease, net
Summary of assets for lease, net	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2023 2022 Assets for lease ​ $ 3,375 ​ $ 3,702 Less: accumulated depreciation ​ (1,090) ​ (1,224) Assets for lease, net ​ $ 2,285 ​ $ 2,478

Property and Equipment, net (Ta

Property and Equipment, net (Tables)	12 Months Ended
	Dec. 31, 2023
Property and Equipment, net
Schedule of property and equipment, net	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ ​ 2023 2022 Property and equipment, gross ​ $ 1,544 ​ $ 1,206 ​ Less: accumulated depreciation ​ (824) ​ (539) ​ Property and equipment, net ​ $ 720 ​ $ 667 ​

Long-Term Investments (Tables)

Long-Term Investments (Tables)	12 Months Ended
	Dec. 31, 2023
Long-Term Investments
Schedule of carrying value of non-marketable equity investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ ​ 2023 2022 ​ Investments in SYNAPS Dx $ 512 ​ $ 512 ​ Investments in Mellitus Health, Inc. ​ ​ - ​ ​ 309 ​ Total long-term investments ​ $ 512 ​ $ 821 ​

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Measurements
Schedule of financial assets measured at fair value on a recurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Hierarchy ​ Level 1 ​ Level 2 ​ Level 3 ​ Total As of December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Government money market fund accounts $ 41,373 ​ $ — ​ $ — ​ $ 41,373 (Included in cash and cash equivalents) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Treasury bills ​ — ​ ​ 10,494 ​ ​ — ​ ​ 10,494 (Included in short-term investments) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment in debt securities ​ — ​ ​ — ​ ​ 4,372 ​ ​ 4,372 (Included in notes held for investment) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Assets $ 41,373 ​ $ 10,494 ​ $ 4,372 ​ $ 56,239 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Level 1 ​ Level 2 ​ Level 3 ​ Total As of December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Treasury bill $ 20,073 ​ $ — ​ $ — ​ $ 20,073 (Included in short-term investments) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment in debt securities ​ — ​ ​ — ​ ​ 3,679 ​ ​ 3,679 (Included in notes held for investment) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total Assets $ 20,073 ​ $ — ​ $ 3,679 ​ $ 23,752
Schedule of key inputs for the valuation model	​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ 2023 ​ Risk-free rate ​ 3.94% - 5.26% ​ Cash flow discount rate ​ 27.8% ​ Expert term in years ​ 0.25- 2.92 ​ Expected volatility ​ 120% ​
Schedule of changes in the notes held for the investments	​ ​ ​ ​ ​ ​ ​ ​ Convertible Notes ​ Balance as of December 31, 2022 ​ $ 3,679 ​ Purchased ​ ​ 1,000 ​ Change in fair value of the notes held for investment ​ ​ (307) ​ Balance as of December 31, 2023 ​ $ 4,372 ​ ​

Notes held for investment (Tabl

Notes held for investment (Tables)	12 Months Ended
	Dec. 31, 2023
Notes held for investment
Schedule of notes receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ December 31, ​ ​ ​ 2023 ​ ​ 2022 ​ Senior secured promissory notes ​ $ 1,000 ​ $ 1,000 ​ Secured convertible promissory notes ​ ​ 4,372 ​ ​ 3,679 ​ Total notes held for investment ​ $ 5,372 ​ $ 4,679 ​

Other Non-current assets (Table

Other Non-current assets (Tables)	12 Months Ended
	Dec. 31, 2023
Other Non-current assets
Schedule of other non-current assets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ ​ 2023 2022 Prepaid licenses ​ ​ $ — ​ $ 2,490 Other ​ ​ ​ 270 ​ ​ 352 Total other non-current assets ​ ​ $ 270 ​ $ 2,842

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2023
Accrued Expenses
Schedule of accrued expenses	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2023 2022 Compensation ​ $ 2,008 ​ $ 2,467 Accrued Taxes ​ ​ 1,991 ​ ​ 1,923 Miscellaneous Accruals ​ 503 ​ 358 Total Accrued Expenses ​ $ 4,502 ​ $ 4,748 ​

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Lessee Arrangements
Schedule of future minimum rental payments required under operating leases	​ ​ ​ ​ ​ ​ Total 2024 ​ 93 2025 ​ 71 Total undiscounted future minimum lease payments ​ 164 Less: present value discount ​ (4) Total lease liabilities ​ 160 Lease expense in excess cash payment ​ (10) Total ROU asset ​ $ 150

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Stockholders' Equity
Schedule of common stock reserved for issuance	​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ 2023 2022 Common stock warrants ​ — 76,875 Stock options ​ 1,813,175 1,471,670 Total ​ 1,813,175 1,548,545

Stock Option Plan (Tables)

Stock Option Plan (Tables)	12 Months Ended
	Dec. 31, 2023
Stock Option Plan
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Number of ​ Weighted ​ Remaining ​ Aggregate ​ ​ Stock Options ​ Average ​ Contractual ​ Intrinsic Value ​ Outstanding Exercise Price Term (In Years) (In Thousands) Balance, December 31, 2022 1,287,847 ​ $ 3.44 3.03 ​ $ 38,053 Options exercised (283,562) ​ ​ 3.36 ​ — ​ ​ — Options granted ​ 17,950 ​ ​ 25.52 ​ 9.53 ​ ​ — Options cancelled ​ (450) ​ ​ — ​ — ​ ​ — Balance, December 31, 2023 1,021,785 ​ $ 3.84 ​ 3.76 ​ $ 41,333 Exercisable as of December 31, 2023 1,001,344 ​ $ 3.38 ​ 2.10 ​ $ 40,964
Schedule of assumptions used to determining the fair value of stock options	​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2023 2022 ​ Expected term (in years) ​ 7 ​ 7 ​ Risk-free interest rate ​ 4.14-4.41 ​ 2.88 ​ Expected volatility ​ 69.0%-79.5% ​ 78.6% ​ Expected dividend rate ​ 0 ​ 0 ​ Fair value of options granted ​ $17.54-$19.04 ​ $22.27 ​
Schedule of stock-based compensation expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31 ​ ​ December 31 ​ ​ 2023 2022 Cost of Revenues ​ ​ ​ $ 8 ​ $ — Engineering and Product Development ​ ​ ​ ​ 53 ​ ​ 45 Sales and Marketing ​ ​ ​ 317 ​ 173 General and Administrative ​ ​ ​ 566 ​ 523 Total ​ ​ ​ $ 944 ​ $ 741 ​

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Taxes
Schedule of components of the (benefit) provision for income taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 Current tax provision: ​ ​ Federal ​ $ 3,576 $ 3,201 State ​ 605 517 Total current tax provision ​ ​ 4,181 ​ ​ 3,718 Deferred tax provision: ​ ​ ​ Federal ​ (680) (373) State ​ 16 22 Total deferred tax provision ​ ​ (664) ​ ​ (351) Total income tax provision ​ $ 3,517 $ 3,367
Schedule of differences between the Company's effective income tax rate and the federal statutory income tax rate	​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 ​ Federal statutory rate 21.00 % 21.00 % State income tax rate, net of federal benefit 2.04 % 2.57 % Stock-based compensation ​ (7.98) % (4.03) % Permanent items (0.71) % (0.93) % Other 0.24 % 0.35 % Effective income tax rate 14.59 % 18.96 %
Schedule of deferred tax assets	​ ​ ​ ​ ​ ​ ​ ​ ​ 2023 2022 Net operating loss carryforwards $ 188 $ 303 Deferred revenue ​ 268 ​ 278 Stock based compensation ​ 385 ​ 529 Accrual and reserves ​ 251 ​ 297 Research and development credits ​ 262 ​ 254 Other ​ ​ 156 ​ ​ 2 Depreciation and amortization ​ ​ 1,450 ​ ​ 633 Lease liability ​ ​ 38 ​ ​ 59 Total gross deferred tax assets ​ 2,998 ​ 2,355 Less valuation allowance ​ — ​ — Net deferred tax assets ​ ​ 2,998 ​ ​ 2,355 Deferred tax liabilities: ​ ​ ​ ​ ​ ​ Right of use assets ​ ​ (36) ​ ​ (56) Total deferred tax liabilities ​ ​ (36) ​ ​ (56) Net deferred tax assets ​ $ 2,962 $ 2,299
Schedule of activity related to unrecognized tax benefits	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross Unrecognized Tax Benefits 2023 ​ Gross Unrecognized Tax Benefits 2022 Unrecognized tax benefits – January 1 ​ $ 401 $ 476 Gross increases related to prior tax positions ​ 4 — Gross decreases related to prior tax positions ​ ​ — ​ ​ (120) Gross increases related to current tax positions ​ 65 45 Unrecognized tax benefits – December 31 ​ $ 470 $ 401

Net Income Per Share, Basic a_2

Net Income Per Share, Basic and Diluted (Tables)	12 Months Ended
	Dec. 31, 2023
Net Income Per Share, Basic and Diluted
Schedule of basic and diluted net EPS	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ ​ 2023 ​ 2022 ​ ​ Shares Net Income EPS Shares Net Income EPS Basic EPS ​ 6,732,806 ​ $ 20,583 ​ $ 3.06 6,726,687 ​ $ 14,325 ​ $ 2.13 Common stock warrants ​ — ​ — ​ — 68,588 ​ — ​ — Common stock options ​ 1,086,353 ​ — ​ — 1,204,475 ​ — ​ — Diluted EPS ​ 7,819,159 ​ $ 20,583 ​ $ 2.63 7,999,750 ​ $ 14,325 ​ $ 1.79 ​

Summary of Significant Accoun_4

Summary of Significant Accounting Policies and Estimates (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Allowance for doubtful accounts	$ 287	$ 109
Net change due to credit losses	178
Impairment charges	309	0
Deferred revenue recognized	1,160	921
Research and Development	$ 5,421	$ 4,407
Employer matching contribution	50%
Maximum contribution of percentage of employee's eligible earnings	6%
Assets for Lease
Property, Plant and Equipment [Line Items]
PPE useful life	36 months	36 months
Machinery & Equipment
Property, Plant and Equipment [Line Items]
PPE useful life	5 years	5 years
Computer Equipment & Software
Property, Plant and Equipment [Line Items]
PPE useful life	3 years	3 years
Furniture & Fixtures
Property, Plant and Equipment [Line Items]
PPE useful life	5 years	5 years

Assets for Lease, net (Details)

Assets for Lease, net (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets for Lease, net
Assets for lease	$ 3,375	$ 3,702
Less: accumulated depreciation	(1,090)	(1,224)
Assets for lease, net	$ 2,285	$ 2,478

Assets for Lease, net - Additio

Assets for Lease, net - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Assets for Lease, net
Depreciation expense	$ 307	$ 386
Reduction to accumulated depreciation for returned and retired items	441	352
Loss on disposal of assets for lease	(369)	(463)
Total assets for lease, net, in use at customer locations	$ 489	$ 518

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Inventory
Inventory balance	$ 445	$ 469

Property and Equipment, net (De

Property and Equipment, net (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property and Equipment, net
Property and equipment, gross	$ 1,544	$ 1,206
Less: accumulated depreciation	(824)	(539)
Property and equipment, net	$ 720	$ 667

Property and Equipment, net - A

Property and Equipment, net - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property and Equipment, net
Depreciation expense	$ 292	$ 203

Long-Term Investments (Details)

Long-Term Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Equity Securities without Readily Determinable Fair Value [Line Items]
Total long-term investments	$ 512	$ 821
Investments in SYNAPS Dx
Equity Securities without Readily Determinable Fair Value [Line Items]
Total long-term investments	$ 512	512
Investments in Mellitus Health, Inc.
Equity Securities without Readily Determinable Fair Value [Line Items]
Total long-term investments		$ 309

Long-Term Investments - Additio

Long-Term Investments - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Oct. 31, 2020	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2020
Equity Securities without Readily Determinable Fair Value [Line Items]
Impairment		$ 309	$ 0
Investments in SYNAPS Dx
Equity Securities without Readily Determinable Fair Value [Line Items]
Impairment		0
Investments in Mellitus Health, Inc.
Equity Securities without Readily Determinable Fair Value [Line Items]
Amount of shares purchased	$ 250
Impairment		309
Promissory note from SYNAPS Dx
Equity Securities without Readily Determinable Fair Value [Line Items]
Principal amount				$ 500
Conversion value		$ 512	512
Convertible promissory note previously issued by Mellitus
Equity Securities without Readily Determinable Fair Value [Line Items]
Principal amount	50
Conversion value			$ 309
Purchase price	$ 59

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands		12 Months Ended
	Oct. 10, 2023	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
U.S. Government money market fund accounts		$ 41,373
Purchase cost		57,869	$ 19,996
Interest income		151	77
U.S. Treasury bill
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Purchase cost	$ 10,414
Interest rate	5.35%
Interest income		80
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
U.S. Government money market fund accounts		41,373
U.S. Treasury bill		10,494	20,073
Investment in debt securities		4,372	3,679
Total Assets		56,239	23,752
Recurring | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
U.S. Government money market fund accounts		41,373
U.S. Treasury bill			20,073
Total Assets		41,373	20,073
Recurring | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
U.S. Treasury bill		10,494
Total Assets		10,494
Recurring | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in debt securities		4,372	3,679
Total Assets		$ 4,372	$ 3,679

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fair Value Measurements
Percentage of probability of equity financing	5%
Percentage of probability of change of control	75%
Percentage of probability of payment at maturity or an insolvency event	20%
Debt securities measured at fair value	$ 4,372	$ 3,679

Fair Value Measurements - Valua

Fair Value Measurements - Valuation model (Details)	Dec. 31, 2023 Y
Risk-free interest rate | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.0394
Risk-free interest rate | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.0526
Cash flow discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.278
Expected term (in years) | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.25
Expected term (in years) | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	2.92
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	1.20

Fair Value Measurements - Chang

Fair Value Measurements - Changes in the notes held for the investments with significant unobservable inputs (Details) - Notes held for investment $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Beginning balance	$ 3,679
Purchased	1,000
Change in fair value of the notes held for investment	(307)
Ending balance	$ 4,372

Notes held for investment (Deta

Notes held for investment (Details)	1 Months Ended			12 Months Ended
	Dec. 31, 2022 USD ($) item	Jun. 30, 2022 USD ($) item	May 31, 2022 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total notes held for investment	$ 4,679,000			$ 5,372,000	$ 4,679,000
Aggregate principal amount				1,000,000
Interest income from promissory notes				449,000	20,000
Changes in fair value					0
Long-term Investments.	821,000			512,000	821,000
Investments in SYNAPS Dx
Accounts, Notes, Loans and Financing Receivable [Line Items]
Long-term Investments.	512,000			512,000	512,000
Investments in Mellitus Health, Inc.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Long-term Investments.	309,000				309,000
Mellitus
Accounts, Notes, Loans and Financing Receivable [Line Items]
Changes in fair value				179,000
Monarch
Accounts, Notes, Loans and Financing Receivable [Line Items]
Changes in fair value				128,000
Senior secured promissory notes
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total notes held for investment	1,000,000			1,000,000	1,000,000
Interest rate (as a percent)		5%
Number of notes receivable | item		2
Term (in years)		3 years
Aggregate principal amount		$ 1,000,000
Senior secured promissory notes | Investments in Mellitus Health, Inc.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Long-term Investments.				1,000,000
Secured convertible promissory note
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total notes held for investment	3,679,000			4,372,000	3,679,000
Secured convertible promissory note | Investments in Mellitus Health, Inc.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Long-term Investments.				0
Secured convertible promissory note | Mellitus
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest rate (as a percent)			10%
Aggregate principal amount			$ 179,000
Fair value of the Debt Securities	179,000				179,000
Secured convertible promissory note | Monarch
Accounts, Notes, Loans and Financing Receivable [Line Items]
Aggregate principal amount				4,500,000
Maximum amount of available funding	5,000,000				5,000,000
Transaction fee	100,000
Remaining amount available to be drawn	$ 500,000				500,000
Option to extend the maturity date | item	2
Period to extend the maturity date	1 year
Fair value of the Debt Securities	$ 3,500,000			$ 4,372,000	$ 3,500,000
Interest rate	10%

Other Non-current assets (Detai

Other Non-current assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Other Non-current assets
Prepaid licenses		$ 2,490
Other	$ 270	352
Total other non-current assets	$ 270	$ 2,842

Other Non-current assets - Addi

Other Non-current assets - Additional Information Details (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Apr. 30, 2021	Dec. 31, 2023	Dec. 31, 2022
Equity Securities without Readily Determinable Fair Value [Line Items]
Term of agreement	5 years
Write off of prepaid software licenses		$ 2,476
ROU asset		$ 150	$ 233
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]		Other Assets, Noncurrent	Other Assets, Noncurrent
Miscellaneous receivables		$ 100	$ 100
Long-term deposits		20	$ 19
Cost of Revenues
Equity Securities without Readily Determinable Fair Value [Line Items]
Write off of prepaid software licenses		$ 2,476
Mellitus
Equity Securities without Readily Determinable Fair Value [Line Items]
Purchase of product licenses	$ 2,500
Mellitus | Prepaid expenses and other current assets
Equity Securities without Readily Determinable Fair Value [Line Items]
Prepaid license purchases	$ 2,500

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued Expenses
Compensation	$ 2,008	$ 2,467
Accrued Taxes	1,991	1,923
Miscellaneous Accruals	503	358
Total Accrued Expenses	$ 4,502	$ 4,748

Concentration of Credit Risk (D

Concentration of Credit Risk (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) item customer	Dec. 31, 2022 USD ($) item customer
Concentration of Credit Risk
Deposits exceeded federal deposit corporation limits	$ 5,465
U.S. treasury bills	10,494
U.S. Government money market fund accounts	41,373
Allowance for doubtful accounts	$ 287	$ 109
Customer concentration risk | Revenue
Concentration of Credit Risk
Number of customers | customer	2	2
Customer concentration risk | Revenue | Customer one
Concentration of Credit Risk
Concentration risk percentage	36%	40.40%
Customer concentration risk | Revenue | Customer two
Concentration of Credit Risk
Concentration risk percentage	34.90%	29%
Customer concentration risk | Accounts receivable
Concentration of Credit Risk
Number of customers | customer	3	3
Customer concentration risk | Accounts receivable | Customer one
Concentration of Credit Risk
Concentration risk percentage	27.50%	26.80%
Customer concentration risk | Accounts receivable | Customer two
Concentration of Credit Risk
Concentration risk percentage	27.50%	25.90%
Customer concentration risk | Accounts receivable | Customer three
Concentration of Credit Risk
Concentration risk percentage	23.60%	16.80%
Vendor concentration risk | Accounts payable
Concentration of Credit Risk
Number of vendors | item	2	2
Vendor concentration risk | Accounts payable | Vendor one
Concentration of Credit Risk
Concentration risk percentage	24%	25.80%
Vendor concentration risk | Accounts payable | Vendor two
Concentration of Credit Risk
Concentration risk percentage	10.10%	10.80%

Leases - Future minimum rental

Leases - Future minimum rental payments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Future minimum rental payments required under operating leases
2024	$ 93
2025	71
Total undiscounted future minimum lease payments	164
Less: present value discount	(4)
Total lease liabilities	160
Lease expense in excess cash payment	(10)
Total ROU asset	$ 150	$ 233

Leases - Lessee Arrangements (D

Leases - Lessee Arrangements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Jul. 31, 2020
Lessee Arrangements
Lease agreement term			61 months
Discount rate			2.50%
Remaining lease term	1 year 9 months
Options to renew	false
Lease expenses	$ 88	$ 88
ROU asset	$ 150	$ 233
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent	Other Assets, Noncurrent
Current lease liabilities	$ 90
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Liabilities, Current
Noncurrent lease liabilities	$ 70
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent

Leases - Lessor Arrangements (D

Leases - Lessor Arrangements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Lessee Arrangements
Lease, Practical Expedient, Lessor Single Lease Component [true false]	true
Lease revenue	$ 37,262	$ 34,039
Operating Lease, Lease Income, Statement of Income or Comprehensive Income [Extensible Enumeration]	Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax

Leases - Variable-fee Revenue (

Leases - Variable-fee Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Lessee Arrangements
Revenue from variable-fee licenses	$ 28,992	$ 21,277
Revenues from sales of hardware and equipment accessories	$ 1,930	$ 1,358

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2022 USD ($) item	Dec. 31, 2023 USD ($)	Dec. 31, 2021 USD ($)
Commitments and Contingencies
Aggregate principal amount		$ 1,000
Retention credit	$ 0	0	$ 1,240
Senior secured convertible promissory note | Monarch
Commitments and Contingencies
Maximum amount of available funding	$ 5,000
Interest rate	10%
Option to extend the maturity date | item	2
Period to extend the maturity date	1 year
Transaction fee	$ 100
Aggregate principal amount		$ 4,500

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	May 17, 2023 USD ($) shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2023 Vote $ / shares shares	Mar. 14, 2022 USD ($)	Jul. 31, 2013 $ / shares shares	Jun. 07, 2012 $ / shares shares
Stockholders Equity Deficit [Line Items]
Common stock, shares authorized		50,000,000	50,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Number of votes for each share | Vote			1
Shares authorized under Share Repurchase Program | $				$ 20,000
Treasury stock acquired (in shares)		148,500
Cost of treasury stock acquired | $		$ 4,991
Common stock warrants
Stockholders Equity Deficit [Line Items]
Number of warrant issued to purchase common stock					60,000	16,875
Warrant exercise price | $ / shares					$ 4.50	$ 4
Common stock warrants | CEO
Stockholders Equity Deficit [Line Items]
Number of warrant issued to purchase common stock	76,875
Warrants repurchased | $	$ 1,949

Stockholders' Equity - Summary

Stockholders' Equity - Summary of shares reserved for issuance (Details) - shares	Dec. 31, 2023	Dec. 31, 2022
Stockholders' Equity
Total	1,813,175	1,548,545
Common stock warrants
Stockholders' Equity
Total		76,875
Stock options
Stockholders' Equity
Total	1,813,175	1,471,670

Stock Option Plan - Additional

Stock Option Plan - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Oct. 31, 2015	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fully vested stock granted		18,048	9,421
Grant date fair value of stock		$ 860	$ 723
Options granted		17,950
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value of options granted			$ 22.27
2014 Stock Incentive Plan | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares issued pursuant to awards granted under plan		3,582,888		450,000
Number of share reserve approved	1,500,000
Maximum term of stock option grants		10 years
Percentage of shares reserve increased	4%
Number of shares available for future stock-based compensation grants		1,813,175
Total unrecognized compensation cost related to non-vested awards		$ 382
Weighted average period of unvested stock awards		3 years 9 months 3 days
Options granted		17,500
2014 Stock Incentive Plan | Employee Stock Option [Member] | Vested one year after the grant date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percent)		25%
Vesting period (in years)		1 year
2014 Stock Incentive Plan | Employee Stock Option [Member] | Each month thereafter contingent upon the participant's continued service beginning on the initial vesting date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percent)		2.08%
2007 Key Person Stock Option Plan | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future stock-based compensation grants		0

Stock Option Plan - Summary of

Stock Option Plan - Summary of the Company's stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of Stock Options Outstanding
Balance, Beginning	1,287,847
Options exercised	(283,562)
Options granted	17,950
Options cancelled	(450)
Balance, Ending	1,021,785	1,287,847
Exercisable, Ending	1,001,344
Weighted Average Exercise Price
Balance, Beginning	$ 3.44
Options exercised	3.36
Options granted	25.52
Balance, Ending	3.84	$ 3.44
Exercisable, Ending	$ 3.38
Weighted Average Remaining Contractual Term, Options Outstanding (in years)	3 years 9 months 3 days	3 years 10 days
Weighted Average Remaining Contractual Term, Options granted (in years)	9 years 6 months 10 days
Weighted Average Remaining Contractual Term, Options Exercisable (in years)	2 years 1 month 6 days
Aggregate Intrinsic Value, Options Outstanding	$ 41,333	$ 38,053
Aggregate Intrinsic Value, Options Exercisable	$ 40,964

Stock Option Plan - Weighted av

Stock Option Plan - Weighted average assumptions used (Details) - Employee Stock Option [Member] - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Stock Incentive Plan
Expected term (in years)	7 years	7 years
Risk-free interest rate, Minimum	4.14%
Risk free interest rate		2.88%
Risk-free interest rate, Maximum	4.41%
Expected volatility, Minimum	69%
Expected volatility		78.60%
Expected volatility, Maximum	79.50%
Expected dividend rate	0%	0%
Fair value of options granted		$ 22.27
Minimum
Stock Incentive Plan
Fair value of options granted	$ 17.54
Maximum
Stock Incentive Plan
Fair value of options granted	$ 19.04

Stock Option Plan - Stock-based

Stock Option Plan - Stock-based compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 944	$ 741
Cost of Revenues
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	8
Engineering and Product Development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	53	45
Sales and Marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	317	173
General and Administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 566	$ 523

Income Taxes - Summary of compo

Income Taxes - Summary of components of the (benefit) provision for income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Current tax provision:
Federal	$ 3,576	$ 3,201
State	605	517
Total current tax provision	4,181	3,718
Deferred tax provision:
Federal	(680)	(373)
State	16	22
Total deferred tax provision	(664)	(351)
Total income tax provision	$ 3,517	$ 3,367

Income Taxes - Summary of diffe

Income Taxes - Summary of differences between the Company's effective income tax rate and the federal statutory income tax (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Taxes
Federal statutory rate	21%	21%
State income tax rate, net of federal benefit	2.04%	2.57%
Stock-based compensation	(7.98%)	(4.03%)
Permanent Items	(0.71%)	(0.93%)
Other	0.24%	0.35%
Effective income tax rate	14.59%	18.96%

Income Taxes - Summary of Defer

Income Taxes - Summary of Deferred tax assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 188	$ 303
Deferred revenue	268	278
Stock based compensation	385	529
Accrual and reserves	251	297
Research and development credits, net of tax reserve	262	254
Other	156	2
Depreciation and amortization	1,450	633
Lease liability	38	59
Total gross deferred tax assets	2,998	2,355
Less valuation allowance		0
Net deferred tax assets	2,998	2,355
Deferred tax liabilities:
Right of use assets	(36)	(56)
Total deferred tax liabilities	(36)	(56)
Net deferred tax assets	$ 2,962	$ 2,299

Income Taxes - Summary of activ

Income Taxes - Summary of activity related to the Company's gross unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Unrecognized tax benefits:
Unrecognized tax benefits - January 1	$ 401	$ 476
Gross increases related to prior tax positions	4	0
Gross decreases related to prior tax positions	0	(120)
Gross increases related to current tax positions	65	45
Unrecognized tax benefits - December 31	$ 470	$ 401

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Tax Credit Carryforward [Line Items]
Net operating loss carryforwards for California	$ 2,607
Unrecognized tax benefits, if recognized, would affect the effective tax rate	470	$ 401
Interest and penalty expenses related to uncertain tax positions	87	30
Research and experimental expenditures, capitalized	4,610	$ 3,387
Federal
Tax Credit Carryforward [Line Items]
NOL carryforwards	$ 0
Company's tax years beginning for examination	3 years
State
Tax Credit Carryforward [Line Items]
Company's tax years beginning for examination	4 years

Net Income Per Share, Basic a_3

Net Income Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Net Income Per Share, Basic and Diluted
Basic shares (in shares)	6,732,806	6,726,687
Common stock warrants (in shares)		68,588
Common stock options (in shares)	1,086,353	1,204,475
Diluted shares (in shares)	7,819,159	7,999,750
Net Income - Basic EPS	$ 20,583	$ 14,325
Net Income - Common stock warrants	0	0
Net Income - Common stock options	0	0
Net Income - Diluted EPS	$ 20,583	$ 14,325
Basic EPS (in dollars per share)	$ 3.06	$ 2.13
Diluted EPS (in dollars per share)	$ 2.63	$ 1.79

Strategic Plan to Streamline _2

Strategic Plan to Streamline Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Sep. 15, 2023
Strategic Plan to Streamline Operations
Percentage of reduction in employee headcount		30%
Expenses accrued for strategic streamlining	$ 734
Expenses paid for strategic streamlining	$ 734

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ 20,583	$ 14,325

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false