Navidea Biopharmaceuticals (NAVB) 10-Q 11 Aug 23 2023 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Aug. 09, 2023
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	001-35076
Entity Registrant Name	NAVIDEA BIOPHARMACEUTICALS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	31-1080091
Entity Address, Address Line One	4995 Bradenton Avenue, Suite 240
Entity Address, City or Town	Dublin
Entity Address, State or Province	OH
Entity Address, Postal Zip Code	43017-3552
City Area Code	614
Local Phone Number	793-7500
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		99,830,635
Entity Central Index Key	0000810509
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Amendment Flag	false
Common Stock [Member]
Document Information [Line Items]
Title of 12(b) Security	Common Stock
Trading Symbol	NAVB
Security Exchange Name	NYSEAMER
Preferred Stock Purchase Rights [Member]
Document Information [Line Items]
Title of 12(b) Security	Preferred Stock Purchase Rights
Trading Symbol	N/A
Security Exchange Name	NYSEAMER

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 6,143,869	$ 1,995,860
Receivables	44,712	630
Inventory, net	460,746	427,344
Prepaid expenses and other	355,215	780,110
Total current assets	7,004,542	3,203,944
Property and equipment	733,145	835,845
Less accumulated depreciation and amortization	610,747	700,498
Property and equipment, net	122,398	135,347
Right-of-use lease assets	24,313	107,243
Less accumulated amortization	4,749	86,943
Right-of-use lease assets, net	19,564	20,300
License agreements, patents and trademarks	1,303,906	1,215,604
Less accumulated amortization	242,372	215,363
License agreements, patents and trademarks, net	1,061,534	1,000,241
Other assets	11,774	11,774
Total assets	8,219,812	4,371,606
Current liabilities:
Accounts payable	2,007,781	2,122,538
Accrued liabilities and other	4,159,946	6,456,762
Notes payable, current	1,319,105	543,613
Lease liabilities, current	19,030	18,976
Deferred revenue, current	800,000	800,000
Total current liabilities	8,305,862	9,941,889
Lease liabilities, net of current portion	534	1,312
Deferred revenue	700,000	700,000
Total liabilities	9,006,396	12,514,916
Stockholders’ deficit:
Common Stock; $.001 par value, 300,000,000 shares authorized; 96,149,385 and 32,687,666 shares issued and outstanding as of June 30, 2023 and December 31, 2022, respectively	287,146	223,684
Additional paid-in capital	382,287,796	379,343,124
Accumulated deficit	(383,654,144)	(388,002,649)
Total stockholders' deficit	(1,079,101)	(8,435,828)
Noncontrolling interest	292,517	292,518
Total Navidea stockholders’ deficit	(786,584)	(8,143,310)
Total liabilities and stockholders’ deficit	8,219,812	4,371,606
Non-Series Preferred Stock [Member]
Stockholders’ deficit:
Preferred stock	0	0
Series G Preferred Stock [Member]
Stockholders’ deficit:
Preferred stock	2	3
Series H Preferred Stock [Member]
Stockholders’ deficit:
Preferred stock	0	0
Series I Preferred Stock [Member]
Stockholders’ deficit:
Preferred stock	4	10
Series D Preferred Stock [Member]
Stockholders’ deficit:
Preferred stock	11	0
Series E Preferred Stock [Member]
Stockholders’ deficit:
Preferred stock	84	0
Related Party [Member]
Current liabilities:
Notes Payable, Noncurrent	$ 0	$ 1,871,715

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized (in shares)	300,000,000	300,000,000
Common Stock, Shares, Issued (in shares)	96,149,385	32,687,666
Common Stock, Shares, Outstanding (in shares)	96,149,385	32,687,666
Non-Series Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares outstanding (in shares)	0	0
Preferred Stock, Shares Issued (in shares)	0	0
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Outstanding (in shares)	0	0
Series G Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	3,260	3,260
Preferred stock, shares outstanding (in shares)	2,270	3,260
Preferred Stock, Shares Issued (in shares)	2,270	3,260
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Outstanding (in shares)	2,270	3,260
Series H Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	75,000	75,000
Preferred stock, shares outstanding (in shares)	0	0
Preferred Stock, Shares Issued (in shares)	0	0
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Outstanding (in shares)	0	0
Series I Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	35,000	35,000
Preferred stock, shares outstanding (in shares)	4,145	9,480
Preferred Stock, Shares Issued (in shares)	4,145	9,480
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Outstanding (in shares)	4,145	9,480
Series J Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	150,000	150,000
Preferred stock, shares outstanding (in shares)	11,000	0
Preferred Stock, Shares Issued (in shares)	11,000	0
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Outstanding (in shares)	11,000	0
Series K Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	150,000	150,000
Preferred stock, shares outstanding (in shares)	83,949	0
Preferred Stock, Shares Issued (in shares)	83,949	0
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Outstanding (in shares)	83,949	0

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue:
Revenue from contract with customer	$ 0	$ 6,519	$ 0	$ 6,519
Grant and other revenue	0	51,007	0	51,007
Total Revenue	0	57,526	0	57,526
Cost of revenue	0	473	0	473
Gross profit	0	57,053	0	57,053
Research and development	1,106,265	1,723,988	2,373,718	2,893,242
Selling, general and administrative	1,321,433	1,255,666	2,476,349	3,065,695
Total operating expenses	2,427,698	2,979,654	4,850,067	5,958,937
Loss from operations	(2,427,698)	(2,922,601)	(4,850,067)	(5,901,884)	[1]
Other income (expense):
Interest income (expense), net	614,380	(83,584)	351,185	(87,246)
Gain on amendment of contracts	0	0	1,226,432	0
Gain on sale of non-financial asset – NAV4694	750,000		750,000
Loss on extinguishment of debt	(185,056)	0	(185,056)	0
Other, net	(144,810)	6,726	(162,008)	2,427
Total other income (expense), net	1,034,514	(76,858)	1,980,553	(84,819)
Loss from continuing operations	(1,393,184)	(2,999,459)	(2,869,514)	(5,986,703)
Discontinued operations, net of tax effect:
Gain on discontinued operations – Lymphoseek®	7,425,000	0	7,425,000	0
Net income (loss)	6,031,816	(2,999,459)	4,555,486	(5,986,703)
Net income attributable to noncontrolling interest	0	1	1	3
Preferred stock dividends	(68,937)	0	(68,937)	0
Deemed dividend on preferred stock exchanged	(138,045)	0	(138,045)	0
Net income (loss) attributable to common stockholders	$ 5,824,834	$ (2,999,458)	$ 4,348,505	$ (5,986,700)
(Loss) income per common share (basic and diluted)
Continuing operations (in dollars per share)	$ (0.03)	$ (0.10)	$ (0.08)	$ (0.20)
Discontinued operations (in dollars per share)	0.15	0	0.19	0
Attributable to common stockholders (in dollars per share)	$ 0.12	$ (0.10)	$ 0.11	$ (0.20)
Weighted average shares outstanding (in shares)	48,242,642	30,268,858	40,491,390	30,238,471
[1]Loss from operations does not reflect the allocation of certain selling, general and administrative expenses, excluding depreciation and amortization, to our individual reportable segments, other than those expenses directly incurred by Navidea Europe, Navidea UK and MT.

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($)	Preferred Stock [Member] Series G Preferred Stock [Member]	Preferred Stock [Member] Series K Preferred Stock [Member]	Preferred Stock [Member] Conversion of Series G Preferred Stock and Accrued Dividends Into Series J Preferred Stock [Member]	Preferred Stock [Member] Conversion from Series I Preferred Stock To Common Stock [Member]	Preferred Stock [Member] Conversion of Series J preferred Stock Into Common Stock [Member]	Preferred Stock [Member]	Common Stock [Member] Series G Preferred Stock [Member]	Common Stock [Member] Series K Preferred Stock [Member]	Common Stock [Member] Conversion of Series G Preferred Stock and Accrued Dividends Into Series J Preferred Stock [Member]	Common Stock [Member] Conversion from Series I Preferred Stock To Common Stock [Member]	Common Stock [Member] Conversion of Series J preferred Stock Into Common Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member] Series G Preferred Stock [Member]	Additional Paid-in Capital [Member] Series K Preferred Stock [Member]	Additional Paid-in Capital [Member] Conversion of Series G Preferred Stock and Accrued Dividends Into Series J Preferred Stock [Member]	Additional Paid-in Capital [Member] Conversion from Series I Preferred Stock To Common Stock [Member]	Additional Paid-in Capital [Member] Conversion of Series J preferred Stock Into Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member] Series G Preferred Stock [Member]	Retained Earnings [Member] Conversion of Series G Preferred Stock and Accrued Dividends Into Series J Preferred Stock [Member]	Retained Earnings [Member] Conversion from Series I Preferred Stock To Common Stock [Member]	Retained Earnings [Member] Conversion of Series J preferred Stock Into Common Stock [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member] Series G Preferred Stock [Member]	Noncontrolling Interest [Member] Series K Preferred Stock [Member]	Noncontrolling Interest [Member] Conversion of Series G Preferred Stock and Accrued Dividends Into Series J Preferred Stock [Member]	Noncontrolling Interest [Member] Conversion from Series I Preferred Stock To Common Stock [Member]	Noncontrolling Interest [Member] Conversion of Series J preferred Stock Into Common Stock [Member]	Noncontrolling Interest [Member]	Series G Preferred Stock [Member]	Series K Preferred Stock [Member]	Conversion of Series G Preferred Stock and Accrued Dividends Into Series J Preferred Stock [Member]	Conversion from Series I Preferred Stock To Common Stock [Member]	Conversion of Series J preferred Stock Into Common Stock [Member]	Total
Balance (in shares) at Dec. 31, 2021						72,077						30,279,922
Balance at Dec. 31, 2021						$ 72						$ 221,277						$ 370,459,705					$ (370,787,610)						$ 731,299						$ 624,743
Issued stock to 401(k) plan (in shares)						0						53,238
Issued stock to 401(k) plan						$ 0						$ 53						44,667					0						0						44,720
Stock compensation expense						0						0						184,850					0						0						184,850
Net income (loss)						$ 0						$ 0						0					(2,987,242)						(3)						(2,987,245)
Issued stock for payment of director fees (in shares)						0						7,500
Issued stock for payment of director fees						$ 0						$ 7						6,518					0						0						6,525
Issued stock in lieu of cash bonuses (in shares)						0						16,632
Issued stock in lieu of cash bonuses						$ 0						$ 17						16,948					0						0						16,965
MT Preferred Stock reacquired due to Platinum settlement						$ 0						$ 0						438,778					0						(438,778)						0
Balance (in shares) at Mar. 31, 2022						72,077						30,357,292
Balance at Mar. 31, 2022						$ 72						$ 221,354						371,151,466					(373,774,852)						292,518						(2,109,442)
Balance (in shares) at Dec. 31, 2021						72,077						30,279,922
Balance at Dec. 31, 2021						$ 72						$ 221,277						370,459,705					(370,787,610)						731,299						$ 624,743
Issued stock to 401(k) plan (in shares)																																			53,238
Issued stock to 401(k) plan																																			$ 44,720
Net income (loss)																																			(5,986,703)
Balance (in shares) at Jun. 30, 2022						27,077						30,364,792
Balance at Jun. 30, 2022						$ 27						$ 221,361						372,019,758					(376,774,310)						292,517						(4,240,647)
Balance (in shares) at Dec. 31, 2021						72,077						30,279,922
Balance at Dec. 31, 2021						$ 72						$ 221,277						370,459,705					(370,787,610)						731,299						624,743
Balance (in shares) at Dec. 31, 2022						12,740						32,687,666
Balance at Dec. 31, 2022						$ 13						$ 223,684						379,343,124					(388,002,649)						292,518						(8,143,310)
Balance (in shares) at Mar. 31, 2022						72,077						30,357,292
Balance at Mar. 31, 2022						$ 72						$ 221,354						371,151,466					(373,774,852)						292,518						(2,109,442)
Stock compensation expense						0						0						40,554					0						0						40,554
Net income (loss)						$ 0						$ 0						0					(2,999,458)						(1)						(2,999,459)
Preferred Stock converted (in shares)						(45,000)						0
Preferred Stock converted						$ (45)						$ 0						821,295					0						0						821,250
Issued stock for payment of director fees (in shares)						0						7,500
Issued stock for payment of director fees						$ 0						$ 7						6,443					0						0						6,450
Balance (in shares) at Jun. 30, 2022						27,077						30,364,792
Balance at Jun. 30, 2022						$ 27						$ 221,361						372,019,758					(376,774,310)						292,517						(4,240,647)
Balance (in shares) at Dec. 31, 2022						12,740						32,687,666
Balance at Dec. 31, 2022						$ 13						$ 223,684						379,343,124					(388,002,649)						292,518						(8,143,310)
Issued stock to 401(k) plan (in shares)						0						163,586
Issued stock to 401(k) plan						$ 0						$ 164						52,184					0						0						52,348
Stock compensation expense						0						0						19,669					0						0						19,669
Net income (loss)						$ 0						$ 0						0					(1,476,329)						(1)						(1,476,330)
Balance (in shares) at Mar. 31, 2023						12,740						32,851,252
Balance at Mar. 31, 2023						$ 13						$ 223,848						379,414,977					(389,478,978)						292,517						(9,547,623)
Balance (in shares) at Dec. 31, 2022						12,740						32,687,666
Balance at Dec. 31, 2022						$ 13						$ 223,684						379,343,124					(388,002,649)						292,518						$ (8,143,310)
Issued stock to 401(k) plan (in shares)																																			163,586
Issued stock to 401(k) plan																																			$ 52,348
Net income (loss)																																			4,555,486
Preferred Stock converted (in shares)				5,335	11,969					33,277,222	11,508,672																							11,969
Deemed dividend on Series G Preferred Stock and Accrued Dividends exchanged for Series J Preferred Stock																																			138,045
Issued stock as partial repayment of debt (in shares)												12,200,000
Issued stock as partial repayment of debt												$ 1,061,400
Balance (in shares) at Jun. 30, 2023						101,364						96,149,385
Balance at Jun. 30, 2023						$ 101						$ 287,146						382,287,796					(383,654,144)						292,517						(786,584)
Balance (in shares) at Mar. 31, 2023						12,740						32,851,252
Balance at Mar. 31, 2023						$ 13						$ 223,848						379,414,977					(389,478,978)						292,517						(9,547,623)
Stock compensation expense																		33,841					0						0						33,841
Net income (loss)						$ 0						$ 0						0					6,031,816						0						6,031,816
Issued stock (in shares)						11,000						6,308,489
Issued stock						$ 11						$ 6,308						1,088,989					0						0						1,089,000
Stock Issued Under Credit, Net of Costs																		593,818																	600,126
Accrued Dividends payable on Series G Preferred Stock	$ 0						$ 0						$ 0						$ 68,853					$ 0						$ 68,853
Preferred Stock converted (in shares)			10,979	(5,335)	(11,969)				0	33,277,222	11,508,672
Preferred Stock converted			$ 11	$ (6)	$ (12)				$ 0	$ 33,277	$ 11,509				$ 68,842	$ (33,271)	$ (11,497)			$ 0	$ 0	$ 0				$ 0	$ 0	$ 0				$ 68,853	$ 0	$ 0
Deemed dividend on Series G Preferred Stock and Accrued Dividends exchanged for Series J Preferred Stock																		138,045					(138,045)						0						$ 0
Issued Series K Preferred Stock dividend (in shares)		83,949						0
Issued Series K Preferred Stock dividend		$ 84						$ 0						$ 0											$ 0						$ 0
Issued stock as partial repayment of debt (in shares)						0						12,200,000																							1,073,600
Issued stock as partial repayment of debt						$ 0						$ 12,200						1,061,400					0						0
Issued stock for payment of director fees (in shares)						0						3,750
Issued stock for payment of director fees												$ 4						334					0						0						$ 338
Balance (in shares) at Jun. 30, 2023						101,364						96,149,385
Balance at Jun. 30, 2023						$ 101						$ 287,146						$ 382,287,796					$ (383,654,144)						$ 292,517						$ (786,584)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net income (loss)	$ 4,555,486	$ (5,986,703)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	54,689	44,649
Non-cash lease expense	18,239	60,929
Loss on abandonment of patent and trademark applications	1,377	62,388
Stock compensation expense	(14,173)	225,404
Value of stock issued to 401(k) plan for employer matching contributions	52,348	44,720
Value of stock issued in payment of employee bonuses	0	16,965
Value of stock issued in payment of director fees	338	12,975
Gain on amendment of contracts	(1,226,432)	0
Loss on extinguishment of debt	(185,056)	0
Amortization of debt discount and issuance costs	197,361	56,182
Receivables	(44,082)	62,924
Inventory	(33,402)	(164,515)
Prepaid expenses and other assets	424,895	411,284
Accounts payable	(114,757)	1,005,335
Accrued and other liabilities	(1,070,383)	(418,347)
Lease liabilities	(18,227)	(175,535)
Deferred revenue	0	45,929
Payments for purchases of equipment	(15,068)	(48,657)
Proceeds from sales of equipment	336	0
Patent and trademark costs	(89,678)	(190,727)
Net cash used in investing activities	(104,410)	(239,384)
Net cash provided by (used in) operating activities	2,968,333	(4,695,415)
Changes in operating assets and liabilities:
Amortization of debt discount and issuance costs	197,361	56,182
us-gaap_IncreaseDecreaseInContractWithCustomerLiability	0	45,929
Cash flows from financing activities:
Proceeds from issuance of preferred stock	1,100,000	0
Proceeds from issuance of Common Stock	643,759	0
Proceeds from note payable	300,000	1,500,000
Payment of debt issuance costs	0	(14,627)
Principal payments on notes payable	(705,040)	(453,427)
Net cash provided by financing activities	1,284,086	1,031,946
Net increase (decrease) in cash and cash equivalents	4,148,009	(3,902,853)
Cash and cash equivalents, beginning of period	1,995,860	4,230,865
Cash and cash equivalents, end of period	6,143,869	328,012
Preferred Stock [Member]
Cash flows from financing activities:
Payment of preferred stock issuance costs	11,000	0
Common Stock [Member]
Cash flows from financing activities:
Payment of preferred stock issuance costs	$ 43,633	$ 0

Note 1 - Summary of Significant

Note 1 - Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Significant Accounting Policies [Text Block]	1. Summary of Significant Accounting Policies a. Basis of Presentation: Our condensed consolidated financial statements include the accounts of Navidea and our wholly owned subsidiaries, Navidea Biopharmaceuticals Europe Limited (“Navidea Europe”) and Navidea Biopharmaceuticals Limited (“Navidea UK”), as well as those of our majority-owned subsidiary, Macrophage Therapeutics, Inc. (“MT”). All significant inter-company accounts were eliminated in consolidation. b. Use of Estimates: c. Revenue Recognition: We also earn revenue from product sales to end customers, primarily in Europe. Revenue from product sales is generally recognized at the point where the customer obtains control of the goods and we satisfy our performance obligation, which occurs upon either shipment of the product or arrival at its destination, depending upon the shipping terms of the transaction. Our customers have no right to return products purchased in the ordinary course of business, however, we may allow returns in certain circumstances based on specific agreements. In addition, we earn revenues related to our licensing and distribution agreements. The consideration we are eligible to receive under our licensing and distribution agreements typically includes upfront payments, reimbursement for research and development (“R&D”) costs, milestone payments, and royalties. Each licensing and distribution agreement is unique and requires separate assessment in accordance with current accounting standards. See Note 3. d. Net Earnings (Loss) Per Share: e. Research and Development Costs: f. Inventory: g. Intangible Assets: h. Leases: i. Contingent Liabilities: Contingencies j. Recently Adopted Accounting Standards: Measurement of Credit Losses on Financial Instruments

Note 2 - Liquidity

Note 2 - Liquidity	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Substantial Doubt about Going Concern [Text Block]	2. Liquidity The Company is engaged in ongoing litigation with CRG. On August 30, 2022, the District Court of Harris County, Texas (the “Texas Court”) awarded CRG approximately $2.6 million in attorney’s fees on their breach of contract claims against Navidea and MT, with post-judgment interest accruing on the award at the rate of 5% per annum, compounded annually. The Company has appealed the Texas Court’s judgment to the Fourteenth Court of Appeals of Texas. As of June 30, 2023, the Company has accrued $2,679,380 of legal fees and interest pursuant to the Texas Court’s ruling. See Note 10. In addition, the Company is engaged in ongoing litigation with our former President and Chief Executive Officer, Dr. Michael Goldberg. See Note 10. The Company has previously entered into an API Development Funding and Access Agreement (“API Development Agreement”) with a strategic partner for assistance with the development and supply of the active pharmaceutical ingredient (“API”) used to manufacture Lymphoseek (technetium Tc 99m tilmanocept) that is sold by the Company in countries other than the United States, Canada and Mexico. Under the API Development Agreement, among other things, the strategic partner agreed to reimburse the Company for up to a total of $1.85 million of the Company’s out-of-pocket costs associated with such development, in two installments, subject to specified commercial and regulatory milestones. On August 11, 2022, the Company received the first installment in the amount of $800,000, which the strategic partner has the right to claw back due to the Company not satisfying certain commercial and regulatory milestones on or before March 31, 2023. The Company remains engaged in consistent communication with the strategic partner regarding this issue and the status of the API Development process. Based on these communications and the strategic partner’s expressed desire and financial and operational motivation for successful completion of the API Development process, the Company does not expect the strategic partner to exercise its claw-back right. The strategic partner is obligated, subject to certain conditions, to pay the remaining reimbursement amount upon the satisfaction of specified commercial and regulatory milestones. On April 10, 2023, the Company entered into an Asset Purchase Agreement (the “Agreement”) with Meilleur Technologies, Inc. (“Meilleur”), pursuant to which Meilleur agreed to acquire certain assets and assume certain liabilities of the Company relating to its business of developing and commercializing PET biomarkers for Alzheimer’s Disease (the “Business”). As part of the purchase price, Meilleur paid a cash payment of $250,000 to the Company at closing and agreed to make a cash payment of $500,000 to the Company within 60 days after the closing date. Both cash payments were made during the second quarter of 2023. In addition, Meilleur agreed to make certain future payments (as part of the purchase price) to the Company, including contingent payments and milestone payments based on potential licensing events, regulatory submissions, regulatory approvals, and net sales of any approved product derived from the purchased Business. The current conflict between Ukraine and Russia has created volatility in the global capital markets and is continuing to have further global economic consequences, including disruptions of the global supply chain and energy markets. Any such volatility and disruptions may have adverse consequences on us or the third parties who operate in Europe on whom we rely. If the equity and credit markets deteriorate, including as a result of political unrest or war, it may make any debt or equity financing more difficult to obtain, more costly or more dilutive. The Company has experienced recurring net losses and has used significant cash to fund its operations. The Company has considerable discretion over the extent of development project expenditures and has the ability to curtail the related cash flows as needed. The Company also continues working to establish new sources of funding, including potential equity and/or debt financings, collaborations and additional grant funding that can augment the balance sheet. However, based on our current working capital and our projected cash burn, management believes that there is substantial doubt about the Company’s ability to continue as a going concern for a period of one year from the filing of this Quarterly Report on Form 10-Q. The Company’s condensed consolidated financial statements do not include any adjustments to the assets carrying amount, to the expenses presented and to the reclassification of the condensed balance sheets items that could be necessary should the Company be unable to continue its operations.

Note 3 - Revenue From Contracts

Note 3 - Revenue From Contracts With Customers and Other Revenue	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Revenue from Contract with Customer [Text Block]	3. Revenue from Contracts with Customers and Other Revenue Navidea is focused on the development and commercialization of precision immunodiagnostic agents and immunotherapeutics. We manage our business based on two primary types of drug products: (i) diagnostic substances, including Tc99m tilmanocept and other diagnostic applications of our Manocept platform, and (ii) therapeutic development programs, including all therapeutic applications of our Manocept platform. Tc99m tilmanocept, which the Company has a license to distribute outside of Canada, Mexico and the United States, is the only one of the Company’s drug product candidates that has been approved for sale in any market. Tc99 tilmanocept has only been approved for sale in the European Union (“EU”), the UK, India and Australia. We earn revenue from product sales to end customers, primarily in Europe. Revenue from product sales is generally recognized at the point where the customer obtains control of the goods and we satisfy our performance obligation, which occurs upon either shipment of the product or arrival at its destination, depending upon the shipping terms of the transaction. Our customers have no right to return products purchased in the ordinary course of business, however, we may allow returns in certain circumstances based on specific agreements. Normal payment terms generally range from 30 to 90 days from invoice date, in accordance with each contract or purchase order. The Company also recognizes revenue from up-front license fees and pre-market milestones after the cash has been received from its customers and the performance obligations have been met. Payments for sales-based royalties and milestones are generally received after the related revenue has been recognized and invoiced. Normal payment terms generally range from 15 to 90 days following milestone achievement or royalty invoice, in accordance with each contract. Up-front and milestone payments received related to our license and distribution agreements in India and China are deferred until Tc99m tilmanocept has been approved by the regulatory authorities and product sales are authorized to commence in each of those countries. The Company received regulatory approval for Tc99m tilmanocept in India in late March 2022, however certain additional approvals, such as an import license and authorization to use an alternative manufacturer, must be obtained prior to commercial sales launch in India. It is not possible to determine with any degree of certainty whether or when regulatory approval for this product will be achieved in China, if at all. In addition, since sales of Tc99m tilmanocept have not yet begun in India or China, there is no basis for estimating whether, to what degree, or the rate at which the product will be accepted and utilized in these markets. Therefore, it is not possible to determine with any degree of certainty the expected sales in future periods in those countries. As such, the Company intends to recognize revenue from up-front and milestone payments on a straight-line basis beginning at the time of commercial sales launch in each country through the end of the initial term of each agreement. The initial term of each agreement is eight ten The transaction price of a contract is the amount of consideration to which the Company expects to be entitled in exchange for transferring promised goods or services to a customer. Transaction prices do not include amounts collected on behalf of third parties (e.g., sales taxes). To determine the transaction price of a contract, the Company considers the terms of the contract. For the purpose of determining transaction prices, the Company assumes that the goods or services will be transferred to the customer as promised in accordance with existing contracts and that the contracts will not be cancelled, renewed, or modified. When estimating a contract’s transaction price, the Company considers all the information (historical, current, and forecasted) that is reasonably available to it and identifies possible consideration amounts. Most of the Company’s contracts with customers include both fixed and variable components of the transaction price. Under those contracts, some or all of the consideration for satisfied performance obligations is contingent on events over which the Company has no direct influence. For example, regulatory approval or product sales volume milestones are contingent upon the achievement of those milestones by the distributor. Additionally, the prices charged to end users of Tc99m tilmanocept, upon which royalty payments are based in India and China, are set by the distributor in each of those countries. The milestone payments have a binary outcome (that is, the Company will either receive all or none of each milestone payment) and can be estimated using the most-likely-amount method. Taking into account the constraint on variable consideration, the Company has assessed the likelihood of achieving the non-sales-based milestone payments in our current contracts and has determined that it is probable the milestones will be achieved and the Company will receive the consideration. Accordingly, it is probable that including those payments in the transaction price will not result in a significant revenue reversal when the contingency is resolved. Therefore, the amount of the non-sales-based milestone payments is included in the transaction price. Royalties are estimated based on the expected value method because they are based on a variable amount of sales representing a range of possible outcomes. However, when taking into account the constraint on variable consideration, the estimate of future royalties included in the transaction price is generally $0. This conclusion is based on the fact that Tc99m tilmanocept is early in the commercial launch process in Europe and Australia, and sales have not yet begun in India or China, therefore there is currently no basis for estimating whether, to what degree, or the rate at which the product will be accepted and utilized in these markets. Similarly, we currently have no basis for estimating whether sales-based milestones will ever be achieved. Accordingly, the Company recognizes revenue from royalties when the related sales occur and from sales-based milestones when they are achieved. Up-front fees, milestones and royalties are generally non-refundable. Therefore, the Company does not estimate expected refunds nor do we adjust revenue downward. The Company will evaluate and update the estimated transaction prices of its contracts with customers at the end of each reporting period. During the three-month and six-month periods ended June 30, 2023 and 2022, the Company recognized revenue from contracts with customers of $0 and $6,519, respectively. During the three-month and six-month periods ended June 30, 2023 and 2022, the Company did not The following table disaggregates the Company’s revenue from contracts with customers for the three-month and six-month periods ended June 30, 2023 and 2022. Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Sales revenue: Tc99m tilmanocept - Europe $ — $ 6,519 $ — $ 6,519 The following economic factors affect the nature, amount, timing and uncertainty of the Company’s revenue and cash flows as indicated: Geographical Location of Customers: Status of Regulatory Approval. Through June 30, 2023, the Company has not The following table shows the opening and closing balances of contract liabilities from contracts with customers for the six-month period ended June 30, 2023. June 30, 2023 December 31, 2022 (unaudited) Total deferred revenue related to contracts with customers, beginning of period $ 700,000 $ 700,000 Total deferred revenue, end of period $ 700,000 $ 700,000 The Company had sales revenue receivable of $0 and $610 outstanding as of June 30, 2023 and December 31, 2022, respectively. The Company had license revenue receivable of $0 outstanding as of June 30, 2023 and December 31, 2022. In addition to revenue from contracts with customers, we also generate revenue from National Institutes of Health (“NIH”) grants to support various product development initiatives. The revenue recognition standard applies to revenue from contracts with customers. A customer is defined as a party that has contracted with an entity to obtain goods or services that are an output of the entity’s ongoing major or central operations in exchange for consideration. The Company’s ongoing major or central operations consist of the development and commercialization of precision immunodiagnostic agents and immunotherapeutics. The NIH and its various institutes are responsible for biomedical and public health research and provide major biomedical research funding to non-NIH research facilities and entities such as Navidea. While the Company will directly benefit from any knowledge gained from the project, there is also a public health benefit provided, which justifies the use of public funds in the form of the grants. Based on the nature of the Company’s operations and the terms of the grant awards, Navidea does not have a vendor-customer relationship with the NIH and the grant awards are outside the scope of the revenue recognition standard. Accordingly, the revenue recognition standard need not be applied to the NIH grants. During the three-month and six-month periods ended June 30, 2022, the Company recognized grant revenue of $51,007. No grant revenue was recognized in the three-month or six-month periods ended June 30, 2023. Finally, we expect to recognize revenue from a strategic development partner up to a total of $1.85 million under the terms of the API Development Agreement. Based on the nature of the Company’s operations and the terms of the API Development Agreement, Navidea does not have a vendor-customer relationship with the strategic partner and amounts received under the API Development Agreement are outside the scope of the revenue recognition standard. Accordingly, the revenue recognition standard need not be applied to the API Development Agreement. The first installment of $800,000 received on August 11, 2022 was included in deferred revenue, current in the condensed consolidated balance sheets as of June 30,2023. See Note 2.

Note 4 - Stock-based Compensati

Note 4 - Stock-based Compensation	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Share-Based Payment Arrangement [Text Block]	4. Stock-Based Compensation For the three-month periods ended June 30, 2023 and 2022, our total stock-based compensation expense, which includes reversals of expense for certain forfeited or cancelled awards, was $ (33,841) (14,172) not A summary of the status of our stock options as of June 30, 2023, and changes during the six-month period then ended, is presented below. Six Months Ended June 30, 2023 Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value Outstanding, January 1, 2023 702,805 $ 4.42 5.5 $ — Granted 1,339,500 0.32 Cancelled/Forfeited (966,465 ) 0.76 Expired (850 ) 61.60 Outstanding, June 30, 2023 1,074,990 $ 2.55 7.1 $ — Exercisable, June 30, 2023 461,115 $ 5.48 3.6 $ — The weighted average grant date fair value per stock option granted during the six-month period ended June 30, 2023 was $0.24. Key assumptions used in the Black-Scholes option pricing model for stock options granted during the six-month period ended June 30, 2023 were the Company’s stock price, an expected volatility rate of 89.47%, a risk-free rate of 3.87%, and an expected life of 5.95 years. A summary of the status of our unvested restricted stock as of June 30, 2023, and changes during the six-month period then ended, is presented below. Six Months Ended June 30, 2023 Number of Shares Weighted Average Grant-Date Fair Value Unvested, January 1, 2023 90,000 $ 0.99 Vested — — Unvested, June 30, 2023 90,000 $ 0.99 As of June 30, 2023, there was $150,429 of total unrecognized compensation expense related to unvested stock-based awards, which we expect to recognize over the remaining weighted average vesting term of 1.72 years.

Note 5 - Earnings (Loss) Per Sh

Note 5 - Earnings (Loss) Per Share	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Earnings Per Share [Text Block]	5. Earnings (Loss) Per Share Diluted earnings (loss) per common share for the six-month periods ended June 30, 2023 and 2022 excludes the effects of 24,423,896 and 1,148,404 common share equivalents, respectively, since such inclusion would be anti-dilutive. The excluded shares consist of common shares issuable upon exercise of outstanding stock options and warrants. The Company’s unvested restricted stock awards contain nonforfeitable rights to dividends or dividend equivalents, whether paid or unpaid (referred to as “participating securities”). Therefore, the unvested restricted stock awards are required to be included in the number of shares outstanding for both basic and diluted earnings (loss) per share calculations. However, due to our loss from continuing operations, 90,000 shares of unvested restricted stock for the six-month periods ended June 30, 2023 and 2022, were excluded in determining basic and diluted loss per share from continuing operations because such inclusion would be anti-dilutive.

Note 6 - Inventory, Net

Note 6 - Inventory, Net	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Inventory Disclosure [Text Block]	6. Inventory, Net The components of inventory, net as of June 30, 2023 and December 31, 2022 are as follows: June 30, 2023 December 31, 2022 Materials $ 27,405 $ 27,405 Work in process 433,341 399,939 Finished goods 131,804 131,804 Reserve for expiring finished goods (131,804 ) (131,804 ) Total inventory, net $ 460,746 $ 427,344 No

Note 7 - Accounts Payable, Accr

Note 7 - Accounts Payable, Accrued Liabilities and Other	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]	7. Accounts Payable, Accrued Liabilities and Other Accounts payable as of June 30, 2023 and December 31, 2022 includes an aggregate of $464,986 and $318,527, respectively, due to related parties for director fees. Accrued liabilities and other as of June 30, 2023 and December 31, 2022 includes an aggregate of $438,657 and $811,544, respectively, due to related parties for accrued separation costs, bonuses, salaries and benefits. The Company pays fees in both cash and stock to non-employee directors. The cash portion of director fees due is included in accounts payable and the stock portion is included in accrued liabilities and other in the condensed consolidated balance sheets as of June 30, 2023 and December 31, 2022. Certain directors elected to defer receipt of cash and stock for director fees until the Company raises sufficient additional capital. Under our license agreements with the University of California, San Diego (“UCSD”), we have exclusive world-wide rights to all diagnostic and therapeutic uses of tilmanocept, other than Tc99m tilmanocept used in lymphatic mapping in the United States, Canada and Mexico which rights are licensed to Cardinal Health 414, LLC (“Cardinal Health”). The UCSD license agreements include obligations for payments related to license fees, milestones, and royalties. As of June 30, 2023, the Company has accrued approximately $259,000 related to the UCSD license agreements for which we have not yet been invoiced. Of this amount, approximately $104,000 is included in accounts payable and $155,000 is included in accrued expenses and other in the condensed consolidated balance sheets. During the six months ended June 30, 2023, the Company reversed approximately $1.2 million of accruals due to an amendment of the UCSD license agreement for the exclusive world-wide rights to all diagnostic and therapeutic uses of tilmanocept (other than Tc99m tilmanocept used in lymphatic mapping). On March 30, 2023 (the “Effective Date”), Dr. Michael Rosol signed a Separation & Release Agreement (the “Separation Agreement”) in connection with his resignation from his position as Chief Medical Officer on April 10, 2023 (the “Separation Date”). Pursuant to the Separation Agreement, among other things, the Company agreed to pay Dr. Rosol a lump sum payment, less all relevant taxes and other withholdings, of $25,000, payable pursuant to normal payroll processes upon the Effective Date. This lump sum payment was paid to Dr. Rosol on April 14, 2023. For purposes of assistance provided to facilitate the smooth transition of the operation and management of the Company for a period of 6 months after the Separation Date, the Company agreed to pay Dr. Rosol $300 per hour, subject to certain limitations. In addition, Dr. Rosol and the Company generally released each other from any and all claims each may have against the other. On March 30, 2023, in conjunction with Dr. Rosol’s separation, the Company entered into a Consulting Services Agreement (“Consulting Agreement”) with G2G Ventures (“G2G”), the executive director of which is Joshua Wilson, a director of the Company. Under the Consulting Agreement, G2G provides executive-level support services to the Company as mutually agreed in one or more statements of work. The Company pays G2G a monthly retainer of $50,000. The Consulting Agreement may be terminated by either party upon 90 days’ notice.

Note 8 - Notes Payable

Note 8 - Notes Payable	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Debt Disclosure [Text Block]	8. Notes Payable Bridge Notes from John K. Scott, Jr. On April 10, 2022, the Company entered into a Stock Exchange Agreement with John K. Scott, Jr., pursuant to which Mr. Scott agreed to make a loan to the Company in the principal amount of up to $2.5 million, of which $1.5 million was funded on the closing date and $1.0 million was funded on July 1, 2022. The outstanding balance of the loan, which is evidenced by a bridge note (“2022 Bridge Note”), bears interest at a rate of 8% per annum, with payments of interest only to be made monthly over a period of two years. All outstanding principal and accrued and unpaid interest under the 2022 Bridge Note is due and payable on the second anniversary of the Stock Exchange Agreement. The Company’s obligations under the 2022 Bridge Note are secured by a first priority security interest in all of the Company’s assets and personal property pursuant to a Security Agreement between Mr. Scott and the Company, entered into at closing of the 2022 Bridge Note (the “2022 Security Agreement”). As consideration and partial inducement for Mr. Scott to enter into the 2022 Bridge Note, the Company exchanged all 50,000 shares of Mr. Scott’s Series E Preferred Stock for 1,740 shares of Series F Preferred Stock and 3,260 shares of Series G Preferred Stock. In accordance with current accounting guidance, the Company recorded a debt discount of $835,876 including $821,250 related to the difference in the value of Mr. Scott’s Series E Preferred Stock and the Series F and Series G Preferred Stock and $14,626 of debt issuance costs. The debt discount is being amortized as non-cash interest expense using the effective interest method over the term of the 2022 Bridge Note. On April 25, 2023, Mr. Scott agreed to make a second loan to the Company in the principal amount of up to $300,000 under the terms of a secured bridge note (“2023 Bridge Note”), of which $225,000 and $75,000 were funded on April 26, 2023 and May 9, 2023, respectively. The Company’s obligations under the 2023 Bridge Note were secured by a first priority security interest in all of the Company’s assets and personal property pursuant to the 2022 Security Agreement, as amended on April 25, 2023 in favor of Mr. Scott. The Company paid the principal balance of $300,000, plus a non-refundable fee of $15,000 and accrued interest of $105, to Mr. Scott at maturity on June 27, 2023. On June 29, 2023, the Company entered into a letter agreement with Mr. Scott to exchange $1,073,600 principal amount of the 2022 Bridge Note for 12,200,000 shares of our Common Stock, based on the closing stock price on June 28, 2023. Pursuant to the exchange, a proportional $185,056 balance of the debt discount was cancelled. The Company recognized a loss on the partial debt extinguishment of $185,056 during the second quarter of 2023. Interest expense related to the 2022 Bridge Note totaled $155,210 and $297,361 during the three-month and six-month periods ended June 30, 2023, respectively. The principal and debt discount balances related to the 2022 Bridge Note were $1,426,400 and $245,868, respectively, as of June 30, 2023. Interest expense related to the 2023 Bridge Note totaled $105 during the three-month and six-month periods ended June 30, 2023. The principal balance of the 2023 Bridge Note was $0 as of June 30, 2023. IPFS Corporation In November 2021, the Company prepaid $565,760 of insurance premiums through the issuance of a note payable to IPFS Corporation (“IPFS”) with an interest rate of 4.36%. The note was payable in five Interest expense related to the IPFS note payable totaled $0 and $414 during the three-month periods ended June 30, 2023 and 2022, respectively. Interest expense related to the IPFS note payable totaled $0 and $4,126 during the six-month periods ended June 30, 2023 and 2022, respectively. The balance of the IPFS note was $0 as of June 30, 2023. AFCO Premium Credit LLC In November 2022, the Company prepaid $608,275 of insurance premiums through the issuance of a note payable to AFCO Premium Credit LLC (“AFCO”) with an interest rate of 7.85%. The note is payable in nine monthly installments of $69,967, with the final payment due in August 2023. Interest expense related to the AFCO note payable totaled $5,401 and $0 during the three-month periods ended June 30, 2023 and 2022, respectively. Interest expense related to the AFCO note payable totaled $14,763 and $0 during the six-month periods ended June 30, 2023 and 2022, respectively. The balance of the AFCO note was $138,573 as of June 30, 2023, and was included in notes payable, current in the condensed consolidated balance sheets. Summary During the three-month periods ended June 30, 2023 and 2022, we recorded interest expense of $160,716 and $83,596, respectively, related to our notes payable. During the six-month periods ended June 30, 2023 and 2022, we recorded interest expense of $312,229 and $87,308, respectively, related to our notes payable. Annual principal maturities of our notes payable are $138,573 and $1.43 million in 2023 and 2024, respectively.

Note 9 - Leases

Note 9 - Leases	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Lessee, Operating Leases [Text Block]	9. Leases We currently lease approximately 5,000 square feet of office space at 4995 Bradenton Avenue, Dublin, Ohio, as our principal offices, at a monthly base rent of $3,012. The current least term expired in June 2023. In June 2023, we executed an amendment to extend the lease term through December 2023 at a monthly base rent of $3,012. In addition, we leased approximately 25,000 square feet of office space at 5600 Blazer Parkway, Dublin, Ohio, formerly our principal offices, at a monthly base rent of $28,149 in 2022. The lease term expired in October 2022 with an option to extend for an additional five years. The Company did not renew this lease. In June 2017, the Company executed a sublease arrangement for the Blazer Parkway space, providing for monthly sublease payments to Navidea of $39,124 through October 2022. We currently lease office equipment at a monthly payment of $136, expiring in October 2024. Total operating lease expense was $9,449 and $35,497 for the three-month periods ended June 30, 2023 and 2022, respectively. Total operating lease expense was $18,897 and $73,173 for the six-month periods ended June 30, 2023 and 2022, respectively. Operating lease expense was recorded in selling, general and administrative expenses on our condensed consolidated statements of operations. The following table presents information about the amount, timing and uncertainty of cash flows arising from the Company’s operating leases as of June 30, 2023. Maturity of Lease Liabilities Operating Lease Payments 2023 (remaining) $ 18,886 2024 1,355 Total undiscounted operating lease payments 20,241 Less imputed interest (677 ) Present value of operating lease liabilities $ 19,564 Balance Sheet Classification Current lease liabilities $ 19,030 Noncurrent lease liabilities 534 Total operating lease liabilities $ 19,564 Other Information Weighted-average remaining lease term for operating leases (in years) 0.6 Weighted-average discount rate for operating leases 10.67 % Cash paid for amounts included in the present value of operating lease liabilities was $18,886 and $187,779 during the six-month periods ended June 30, 2023 and 2022, respectively, and is included in operating cash flows in the condensed consolidated statements of cash flows.

Note 10 - Commitments and Conti

Note 10 - Commitments and Contingencies	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	10. Commitments and Contingencies We are subject to legal proceedings and claims that arise in the ordinary course of business. In accordance with ASC Topic 450, Contingencies CRG Litigation The Company has been engaged in ongoing litigation with CRG, in its capacity as a lender and as control agent for other affiliated lenders party to the CRG Loan Agreement (collectively, the “CRG Lenders”), in the Texas Court relating to CRG’s claims of default under the terms the CRG Loan Agreement. Following a trial in December 2017, the Texas Court ruled that the Company’s total obligation to CRG was in excess of $66.0 million, limited to $66.0 million under the Global Settlement Agreement (“GSA”) dated March 3, 2017. The Texas Court acknowledged only the $59.0 million payment made in March 2017, concluding that the Company owed CRG another $7.0 million, however the Texas Court did not expressly take the Company’s June 2016 payment of $4.1 million into account and awarded, as part of the $66.0 million, amounts that had already been paid as part of the $4.1 million. The Company believes that this $4.1 million should be credited against the $7.0 million and has appealed the Texas Court’s judgment. The Court of Appeals dismissed the Company’s appeal without reaching the merits due to a contractual waiver of appeal. In April 2018, CRG asserted claims against Navidea and MT for alleged breaches of the GSA and Loan Agreement entered into by Navidea arising from Navidea’s challenge to CRG’s drawing down on letters of credit in the full amount of $7,153,000. Navidea claimed such draw down resulted in an overpayment of approximately $4.2 million under the Loan Agreement. CRG also sought declaratory judgment relief that essentially mirrored their claims for affirmative relief, i.e., that the Company breached the GSA and indemnification provision of the Loan Agreement, and that CRG did not breach the GSA. On November 21, 2021, the Texas Court entered an interlocutory judgment declaring that CRG did not breach the GSA, but that Navidea did breach the GSA and the indemnification provision of the CRG Loan Agreement. In the interlocutory order, the Texas Court sua sponte awarded as damages reasonable attorneys' fees in an amount, if any, to be determined at trial. CRG made a claim of approximately $2.8 million in attorneys' fees they contend they are entitled to in connection with the alleged breaches of the agreements. Navidea contends CRG have received payments in excess of the amounts owed under the CRG Loan Agreement and are not entitled to an award of attorney’s fees under the GSA or Loan Agreement. On August 30, 2022, the Texas Court made an oral ruling from the bench at the conclusion of the trial, awarding CRG approximately $2.6 million in attorney’s fees on their breach of contract claims against Navidea and MT with post-judgment interest accruing on the award at the rate of 5% per annum compounded annually. A formal written final judgment was entered by the Texas Court on August 31, 2022, however, the written judgment did not identify the basis and reasoning in support of the decision. On September 9, 2022, Navidea filed a request for findings of fact and conclusions of law, asking that the Texas Court state in writing the facts found by the Court and the Court’s conclusions of law. On October 11, 2022, the Texas Court filed their findings of fact and conclusions of law, which includes conclusions of law that the amounts due are subject to an interest rate of 18% per annum. The Company has objected to many of the findings of fact and conclusions of law and to any attempt to amend the final judgment as being untimely. The Company has appealed the Texas Court’s judgment to the Fourteenth Court of Appeals of Texas. Despite its objections and pending appeal, and based in part on the ambiguity of language in the Final Judgement and the Findings and Conclusions, as well as the potential for any appeals or re-filing of motions by CRG, the Company recorded accrued interest on the judgement at a rate of 18% as of September 30, 2022. During the second quarter of 2023, the Company received additional clarification and confirmation from its outside counsel that the Texas Court’s judgment remains unchanged, and the stated post-judgment interest rate is 5% per annum compounded annually. Texas Court’s judgment remains unchanged, and the stated post-judgment interest rate is 5% per annum compounded annually. Based on this new information, the Company adopted a change in accounting estimate with regard to the interest rate, from 18% to 5% during the second quarter of 2023, resulting in a downward adjustment to accrued interest and interest expense of $771,000. As of June 30, 2023, the Company has accrued approximately $2.7 million of legal fees and interest pursuant to the Texas Court’s ruling. Goldberg Agreement and Litigation In August 2018, Dr. Goldberg resigned from his positions as an executive officer and a director of Navidea. In connection with Dr. Goldberg’s resignation, Navidea and Dr. Goldberg entered into an Agreement (the “Goldberg Agreement”) which set forth the terms of the separation from service. Among other things, the Goldberg Agreement provided that Dr. Goldberg would be entitled to 1,175,000 shares of our Common Stock, representing in part payment of accrued bonuses and payment of the balance of the Platinum debt. A portion of the 1,175,000 shares to be issued to Dr. Goldberg would be held in escrow for up to 18 months in order to reimburse Navidea in the event that Navidea is obligated to pay any portion of the Platinum debt to a party other than Dr. Goldberg. Further, the Goldberg Agreement provided that the Company’s subsidiary, MT, would redeem all of Dr. Goldberg’s preferred stock and issue to Dr. Goldberg super voting Common Stock equal to 5% of the outstanding shares of MT. In November 2018, the Company issued 925,000 shares of our Common Stock to Dr. Goldberg, 250,000 of which were placed in escrow in accordance with the Goldberg Agreement. On February 11, 2019, Dr. Goldberg represented to the MT Board of Directors (the “MT Board”) that he had, without MT Board or shareholder approval, created a subsidiary of MT, transferred all of the assets of MT into the subsidiary, and then issued himself stock in the subsidiary. On February 19, 2019, Navidea notified MT that it was terminating the sublicense in accordance with its terms, effective March 1, 2019, due to MT’s insolvency. On February 20, 2019, the MT Board removed Dr. Goldberg as President and Chief Executive Officer of MT and from any other office of MT to which he may have been appointed or in which he was serving. Dr. Goldberg remains a member of the MT Board, together with John K. Scott, Jr., who is also the Vice Chair of the Board of Directors of Navidea. On or about February 17, 2022, the Joint Official Liquidators and Foreign Representatives of PPVA executed the necessary paperwork to transfer its preferred stock in MT to Navidea. New York Litigation Involving Dr. Goldberg On February 20, 2019, Navidea filed a complaint against Dr. Goldberg in the United States District Court, Southern District of New York (the “District Court”), alleging breach of the Goldberg Agreement, as well as a breach of the covenant of good faith and fair dealing and to obtain a declaratory judgment that Navidea’s performance under the Goldberg Agreement is excused and that Navidea is entitled to terminate the Goldberg Agreement as a result of Dr. Goldberg’s actions. On April 26, 2019, Navidea filed an amended complaint against Dr. Goldberg which added a claim for breach of fiduciary duty seeking damages related to certain actions Dr. Goldberg took while CEO of Navidea. On June 13, 2019, Dr. Goldberg answered the amended complaint and asserted counterclaims against Navidea and third-party claims against MT for breach of the Goldberg Agreement, wrongful termination, injunctive relief, and quantum meruit. On December 26, 2019, the District Court ruled on several motions related to Navidea and MT and Dr. Goldberg that substantially limited the claims that Dr. Goldberg can pursue against Navidea and MT. Specifically, the District Court found that certain portions of Dr. Goldberg’s counterclaims against Navidea and third-party claims against MT failed to state a claim upon which relief can be granted. Additionally, the District Court ruled that actions taken by Navidea and MT, including reconstituting the MT Board, replacing Dr. Goldberg with Mr. Latkin as Chief Executive Officer of MT, terminating the sublicense between Navidea and MT, terminating certain research projects, and allowing MT intellectual property to revert back to Navidea, were not breaches of the Goldberg Agreement. The District Court also rejected Dr. Goldberg’s claim for wrongful termination as Chief Executive Officer of MT. In addition, the District Court found that Dr. Goldberg lacked standing to seek injunctive relief to force the removal of Dr. Claudine Bruck and Michael Rice from the MT Board, to invalidate all actions taken by the MT Board on or after November 29, 2018 (the date upon which Dr. Bruck and Mr. Rice were appointed by Navidea to the MT Board), or to reinstate the terminated sublicense between Navidea and MT. In addition, the District Court found Navidea’s breach of fiduciary duty claim against Dr. Goldberg for conduct occurring more than three years prior to the filing of the complaint to be time-barred and that Dr. Goldberg is entitled to an advancement of attorneys’ fees solely with respect to that claim. To avoid further litigation expenses, the Company agreed to indemnify Dr. Goldberg solely with respect to the breach of fiduciary duty claim. On January 31, 2020, Goldberg filed a motion for leave to amend his complaint to add back in claims for breach of contract, breach of the implied covenant of good faith and fair dealing, quantum meruit and injunctive relief. On April 1, 2020, the District Court denied Dr. Goldberg’s motion for leave to amend in its entirety. On January 27, 2020, Dr. Goldberg filed a motion seeking additional advancement from Navidea for fees in connection with the New York Action and the Delaware Action. Navidea opposed the motion and the District Court referred the matters to a Magistrate Judge. On July 9, 2020, the Magistrate Judge issued her Report and Recommendation which recommended that: (1) the District Court decline to exercise jurisdiction over Dr. Goldberg’s motion as it pertained to expenses and fees incurred in defense of the Delaware Action; (2) the District Court decline to award any fees to Dr. Goldberg for the breach of fiduciary duty without additional motion practice on the issue; (3) the District Court find that Dr. Goldberg is entitled to advancement of his expenses and fees reasonably incurred in the defense of the remainder of the New York action subject to Dr. Goldberg’s posting of an undertaking; and (4) establish a protocol by which Dr. Goldberg could establish the amounts due for advancement. On August 24, 2020, in connection with Dr. Goldberg’s motion for advancement, the District Court adopted the Magistrate Judge’s report and recommendation and found that while Dr. Goldberg was not being granted advancement of fees and expenses incurred in connection with either the Delaware Action or the assertion of third-party claims against MT, the Court ruled that Dr. Goldberg was entitled to advancement for the defense of the remaining claims asserted against him by Navidea in the New York action. The Court adopted a protocol by which additional motion practice will occur to determine the appropriate amount of fees to be advanced. Once that decision is made by the Magistrate Judge, subject to review by the District Court, Navidea will need to advance those fees to Dr. Goldberg conditioned upon Dr. Goldberg agreeing to pay those fees back to Navidea if it is determined that he is not entitled to indemnification. On May 27, 2021, the District Court ordered that: (1) Dr. Goldberg be awarded $14,955 for indemnification for his attorneys’ fees for his defense of the breach of fiduciary duty claim; (2) Dr. Goldberg be advanced $ 1,237.50 On August 6, 2021, the Company moved for reconsideration of its obligations to advance fees. On October 14, 2021, the Magistrate Judge recommended that Navidea’s motion for reconsideration be denied. On March 7, 2022, the District Court adopted the Report and Recommendation in part and permitted Dr. Goldberg to seek advancement for his fees incurred in defense of his claims since September 1, 2020. On April 8, 2022, Dr. Goldberg submitted a fee application seeking advancement of $ 143,172.55 Fact discovery and expert discovery in the New York Action have been completed. The Company moved to disqualify Dr. Goldberg’s damages expert. On November 9, 2022, the District Court issued an opinion granting the Company’s motion in part and precluding Dr. Goldberg’s damages expert from testifying on all but two issues. On July 20, 2023, the parties submitted motions for summary judgment each requesting that summary judgment be granted in their favor and dismissing the other parties’ affirmative claims. No trial date has been set. NYSE American Continued Listing Standards On January 28, 2022, the Company received a notice from the NYSE American LLC (the “NYSE American”) stating that the Company was not in compliance the $6.0 million stockholders’ equity requirement of Section 1003(a)(iii) of the NYSE American Company Guide. As required by the NYSE American, the Company submitted a plan to the NYSE American by February 28, 2022 advising of actions it has taken or will take to regain compliance with the continued listing standards by July 28, 2023. On April 8, 2022, the Company received a notification (the “Acceptance Letter”) from the NYSE American that the Company’s plan to regain compliance was accepted. The Acceptance Letter also stated that the Company is also not in compliance with Sections 1003(a)(i) and 1003(a)(ii) of the NYSE American Company Guide, which require an issuer to have stockholders’ equity of (i) $2.0 million or more if it has reported losses from continuing operations and/or net losses in two out of its three most recent fiscal years, and (ii) $4.0 million or more if it has reported losses from continuing operations in three out of its four most recent fiscal years. The Acceptance Letter noted that the Company had stockholders’ equity of $624,743 as of December 31, 2021 and has reported net losses from continuing operations in its five most recent fiscal years ended December 31, 2021. The NYSE American granted the Company a plan period through July 28, 2023 to regain compliance with Sections 1003(a)(i), (ii) and (iii). On July 28, 2023, the Company received written notification from NYSE American stating that the staff of NYSE Regulation has determined to commence proceedings to delist the Company’s Common Stock. NYSE Regulation has determined that the Company is no longer suitable for listing pursuant to Section 1009(a) of the NYSE American Company Guide as the Company was unable to demonstrate that it had regained compliance with Sections 1003(a)(i), (ii) and (iii) of the NYSE American Company Guide by the end of the maximum 18-month compliance plan period, which expired on July 28, 2023. The NYSE American’s application with the SEC to delist the Company’s Common Stock is pending, subject to completion of all applicable procedures, including any appeal by the Company of the NYSE Regulation staff’s decision. On August 4, 2023, the Company filed a written request to appeal the NYSE Regulation staff’s decision. There can be no assurance that the Company’s request for continued listing will be granted. The Company’s Common Stock will continue to be listed and traded on NYSE American during the pendency of the Company’s appeal, subject to NYSE American’s discretion to immediately suspend trading if it believes suspension to be in the public interest, for the protection of investors, or to promote just and equitable principles of trade. On June 1, 2023, the Company received a second notice (the “Notice”) from NYSE American indicating that the Company is not in compliance with the NYSE American continued listing standard set forth in Section 1003(f)(v) of the NYSE American Company Guide because its shares of Common Stock have been selling for a substantial period of time at a low price per share. The Notice has no immediate effect on the listing or trading of the Company’s Common Stock and the Common Stock will continue to trade on the NYSE American under the symbol “NAVB,” although a “below compliance” indicator will be appended to the Company’s ticker symbol during the period that it is out of compliance. Pursuant to Section 1003(f)(v) of the NYSE American Company Guide, the NYSE American staff determined that the Company’s continued listing is predicated on it effecting a reverse stock split of its Common Stock or otherwise demonstrating sustained price improvement within a reasonable period of time, which the staff determined to be no later than December 1, 2023. The Notice further stated that as a result of the foregoing, the Company has become subject to the procedures and requirements of Section 1009 of the NYSE American Company Guide, which could, among other things, result in the initiation of delisting proceedings, unless the Company cures the deficiency in a timely manner. The Company intends to regain compliance with the continued listing standards set forth in Section 1003(f)(v) by undertaking a measure or measures that are for the best interests of the Company and its shareholders, including a potential reverse stock split approved by the Company’s stockholders at the special meeting of stockholders held on July 27, 2023.

Note 11 - Equity

Note 11 - Equity	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Equity [Text Block]	11. Equity Amendment to NOL Rights Agreement On April 7, 2022, the Company’s Board of Directors (the “Board”) adopted an NOL rights plan in the form of a Section 382 Rights Agreement (“NOL Rights Agreement”) to preserve and protect the Company’s net operating loss carryforwards (“NOLs”) and other tax assets. As of December 31, 2022, the Company had approximately $175 million of NOLs available to offset future federal taxable income. Under the NOL Rights Agreement, the Board declared a non-taxable dividend of one preferred share purchase right for each outstanding share of Common Stock of the Company, each right initially representing the right to purchase one one-thousandth On January 10, 2023, the Board approved the First Amendment to Section 382 Rights Agreement (“NOL Rights Agreement Amendment”), which reduced the Exchange Ratio from five shares of Common Stock per right to three shares of Common Stock per right. No other terms of the NOL Rights Agreement were amended. The rights issued under the NOL Rights Agreement, as amended, will expire on the earliest of (i) April 6, 2025; (ii) the effective date of the repeal of Section 382 or any successor statute if the Board determines in its sole discretion that the amended NOL Rights Agreement is no longer necessary or desirable for the preservation of NOLs or other tax benefits; (iii) the first day of a taxable year of the Company to which the Board determines in its sole discretion that no NOLs or other Tax Benefits may be carried forward; or (iv) the day following the certification of the voting results of the Company’s 2022 annual meeting of stockholders if at or before such annual meeting a proposal to approve the NOL Rights Agreement has not been approved by stockholders, unless the Rights are earlier redeemed or exchanged by the Company, or upon the occurrence of certain transactions. 401(k) Employer Match During the six-month periods ended June 30, 2023 and 2022, we issued 163,586 and 53,238 shares of our Common Stock as matching contributions to our 401(k) Plan, which were valued at $52,348 and $44,720, respectively. Long Term Incentive Plan On September 9, 2022, the Board approved and adopted the terms and conditions of a long-term incentive plan (“LTIP”) that seeks to motivate and reward employees. The LTIP provides for the issuance of share-based awards to employees of the Company pursuant to the 2014 Plan. The target amount of the stock award under the LTIP for each employee was determined based on a variety of factors. Payout of the stock awards is based on the achievement of pre-established performance objectives and goals related to financing and U.S. Food and Drug Administration (“FDA”) and European Medicines Agency (“EMA”) regulatory milestones for the Company’s Phase 3 clinical trial for rheumatoid arthritis (NAV3-33). The financing and EMA regulatory milestones will each comprise 5% of the total stock award payout for participants; the FDA regulatory milestones will comprise the remaining 90%. The payout amount is subject to downward adjustment based on the timing of the achievement of the particular milestone. In order to receive the payout, the participant generally will be required to continue to be employed through the date of the payout. Although the Company did not fully satisfy the financing milestone, based on completion of the Rights Offering in August 2022 (“2022 Rights Offering”), the Board decided to pay out 5% of the target stock award to all participants under the LTIP. During the year ended December 31, 2022, we issued 70,500 shares of Common Stock to all participants under the LTIP, which were valued at $19,740. Upon issuance of the stock awards, the participants were 100% vested in the stock awards. On March 10, 2023, the Board amended the LTIP to award all 1,339,500 remaining unearned LTIP stock awards as stock options. The LTIP stock options have an exercise price of $0.32 per share and will expire on the tenth Stock Purchase Agreement On April 26, 2023, the Company entered into a Common Stock Purchase Agreement (the “Purchase Agreement”) with Keystone Capital Partners, LLC (“Keystone”) whereby the Company may offer and sell, from time to time at its sole discretion, and whereby Keystone committed to purchase, up to $2,750,000 of shares of the Company’s Common Stock (but subject to certain limitations and conditions). Under the Purchase Agreement, the Company agreed to issue to Keystone 400,000 shares of Common Stock as consideration for its commitment to purchase shares under the Purchase Agreement, with 200,000 shares (based on the closing stock price of $0.25 as of April 25, 2023) being delivered on the date of the Purchase Agreement and the remaining 200,000 shares (based on the closing stock price of $0.25 as of April 25, 2023) to be delivered upon the Company raising a minimum of $2,750,000 under the Purchase Agreement or any other source. Concurrently with entering into the Purchase Agreement, the Company also entered into a registration rights agreement with Keystone, pursuant to which it agreed to provide Keystone with certain registration rights related to the shares issued under the Purchase Agreement. On May 10, 2023, the Company entered into a letter agreement with Keystone, confirming and agreeing that the Company would not issue, and Keystone would not purchase, any shares under the Purchase Agreement in excess of 6,567,409 shares of Common Stock, which represents 19.99% of the shares of the Common Stock outstanding immediately prior to the execution of the Purchase Agreement, unless (i) the Company obtains stockholder approval to do so or (ii) the price per share paid equals or exceeds the greater of book value or market value of the Company’s Common Stock. Between May 3, 2023 and May 25, 2023, the Company sold a total of 6,108,489 shares of Common Stock to Keystone under the Purchase Agreement, generating net proceeds of $600,126. As a result of these Dilutive Issuances (as defined in the Certificate of Designation for the Series I Preferred Stock and the related Warrants issued in the 2022 Rights Offering), the conversion price of the Series I Preferred Stock and the exercise price of the Warrants have been adjusted to $0.16 per share. Based on the adjusted conversion price, each share of the Series I Preferred Stock is convertible into 6,250 shares of Common Stock. Series J Preferred Stock On May 22, 2023, the Company entered into Stock Purchase Agreements (each, a “Purchase Agreement”) with two accredited investors, pursuant to which the Company agreed to issue and sell to the investors in a private placement a total of 11,000 shares of Series J Convertible Preferred Stock, par value $0.001 per share (“Series J Preferred Stock”), for an aggregate purchase price of $1,100,000. Under each Purchase Agreement, the Company also agreed to provide the investors with certain registration rights related to the resale of the shares of the Company’s Common Stock issuable upon conversion of the Series J Preferred Stock. The Company filed a certificate of designation (the “Series J Certificate of Designation”) with the Secretary of State of Delaware designating the rights, preferences and limitations of the shares of Series J Preferred Stock on May 22, 2022. The Series J Certificate of Designation authorizes 150,000 shares of Series J Preferred Stock. The Series J Preferred Stock will be convertible into a number of shares of Common Stock equal to the original issuance price divided by $0.104, subject to adjustment as provided in the Certificate of Designation. However, the holder may not convert shares of the Series J Preferred Stock if, as a result of such conversion, the holder would beneficially own more than 4.99% of the total number of shares of Common Stock outstanding at such time unless the holder of Series J Preferred Stock obtains the prior written consent of the Company (which consent the Company may withhold in its sole absolute discretion). Except with respect to transactions which may adversely affect any right, preference, privilege or voting power of the Series J Preferred Stock, the Series J Preferred Stock has no voting rights. If dividends are declared on the Common Stock, the holder of Series J Preferred Stock will be entitled to receive an amount equal to the dividend declared on one share of Common Stock multiplied by the number of shares of Common Stock into which the Series J Preferred Stock could be converted on the record date, without regard to any conversion limitations. Upon any liquidation, the holder of Series J Preferred Stock will be entitled to receive, before any assets may be distributed to the holders of Common Stock, an amount per share of Series J Preferred Stock calculated by taking the total amount available for distribution to holders of all of the Company’s outstanding Common Stock divided by the total of (x) all of the then outstanding shares of the Company’s Common Stock plus (y) all of the shares of the Company’s Common Stock into which all of the outstanding shares of the Series J Preferred Stock can be converted, and then (z) multiplying the sum so obtained by the number of shares of Common Stock into which such share of Series J Preferred Stock could then be converted. Stock Exchange Agreement On June 1, 2023, the Company entered into a Stock Exchange Agreement with John K. Scott, Jr., pursuant to which Mr. Scott surrendered 990 shares of Series G Redeemable Preferred Stock (“Series G Preferred Stock”) and $68,853 of accrued and unpaid dividends thereon in exchange for 11,969 shares of Series J Preferred Stock. In accordance with U.S. GAAP, we determined that the fair value of the Series G Preferred Stock and accrued and unpaid dividends thereon that were surrendered pursuant to the Stock Exchange Agreement was approximately $1,058,853. The total fair value of the Series J Preferred Stock that was issued in exchange for the Series G Preferred Stock and accrued and unpaid dividends thereon was $1,196,900. Therefore, the incremental fair value received by Mr. Scott was approximately $138,045. The incremental amount was recognized as a deemed dividend during the second quarter of 2023. Pursuant to the Stock Exchange Agreement, Mr. Scott also agreed to surrender his remaining 2,270 shares of Series G Preferred Stock and the remaining balance of accrued and unpaid dividends thereon in exchange for 27,889 shares of Series J Preferred Stock, subject to the Company’s stockholders approving the issuance of shares of the Company’s Common Stock upon conversion of such shares of series J Preferred Stock in compliance with NYSE American listing standards. In addition, the Stock Exchange Agreement provides Mr. Scott with certain registration rights related to the resale of the shares of Common Stock issuable upon conversion of the Series J Preferred Stock. On June 6, 2023, Mr. Scott converted 11,969 shares of Series J Preferred Stock into 11,508,672 shares of the Company’s Common Stock. Series K Preferred Stock On June 16, 2023, the Board declared a dividend of one one-thousandth of a share of Series K Preferred Stock, par value $0.001 per share (“Series K Preferred Stock”), for each outstanding share of the Company’s Common Stock to stockholders of record at 5:00 p.m. Eastern Time on June 27, 2023 (the “Record Date”). Shares of Series K Preferred Stock will be uncertificated and represented in book-entry form. No shares of Series K Preferred Stock may be transferred by the holder thereof except in connection with a transfer by such holder of any shares of Common Stock held by such holder, in which case a number of one one-thousandths (1/1,000ths) of a share of Series K Preferred Stock equal to the number of shares of Common Stock to be transferred by such holder will be automatically transferred to the transferee of such shares of Common Stock. Each share of Series K Preferred Stock will entitle the holder thereof to 1,000,000 votes per share (and, for the avoidance of doubt, each fraction of a share of Series K Preferred Stock will have a ratable number of votes). Thus, each one-thousandth of a share of Series K Preferred Stock would entitle the holder thereof to 1,000 votes. The outstanding shares of Series K Preferred Stock will vote together with the outstanding shares of Common Stock of the Company as a single class exclusively with respect to any proposal to adopt an amendment to the Company’s Amended and Restated Certificate of Incorporation, as amended (the “Certificate of Incorporation”), to reclassify the outstanding shares of Common Stock into a smaller number of shares of Common Stock at a ratio specified in or determined in accordance with the terms of such amendment (the “Reverse Stock Split”). The Series K Preferred Stock will not be entitled to vote on any other matter, except to the extent required under the Delaware General Corporation Law. Unless otherwise provided on any applicable proxy or ballot with respect to the voting on the Reverse Stock Split, the vote of each share of Series K Preferred Stock (or fraction thereof) entitled to vote on the Reverse Stock Split or any other matter brought before any meeting of stockholders held to vote on the Reverse Stock Split will be cast in the same manner as the vote, if any, of the share of Common Stock (or fraction thereof) in respect of which such share of Series K Preferred Stock (or fraction thereof) was issued as a dividend is cast on the Reverse Stock Split or such other matter, as applicable, and the proxy or ballot with respect to shares of Common Stock held by any holder on whose behalf such proxy or ballot is submitted will be deemed to include all shares of Series K Preferred Stock (or fraction thereof) held by such holder. Holders of Series K Preferred Stock will not receive a separate ballot or proxy to cast votes with respect to the Series K Preferred Stock on the Reverse Stock Split or any other matter brought before any meeting of stockholders held to vote on the Reverse Stock Split. The holders of Series K Preferred Stock, as such, will not be entitled to receive dividends of any kind. The Series K Preferred Stock will rank senior to the Common Stock as to any distribution of assets upon a liquidation, dissolution or winding up of the Company, whether voluntarily or involuntarily (a “Dissolution”). Upon any Dissolution, each holder of outstanding shares of Series K Preferred Stock will be entitled to be paid out of the assets of the Company available for distribution to stockholders, prior and in preference to any distribution to the holders of Common Stock, an amount in cash equal to $0.001 per outstanding share of Series K Preferred Stock. All shares of Series K Preferred Stock that are not present in person or by proxy at any meeting of stockholders held to vote on the Reverse Stock Split as of immediately prior to the opening of the polls at such meeting (the “Initial Redemption Time”) will automatically be redeemed in whole, but not in part, by the Company at the Initial Redemption Time without further action on the part of the Company or the holder of shares of Series K Preferred Stock (the “Initial Redemption”). Any outstanding shares of Series K Preferred Stock that have not been redeemed pursuant to an Initial Redemption will be redeemed in whole, but not in part, (i) if such redemption is ordered by the Board in its sole discretion, automatically and effective on such time and date specified by the Board in its sole discretion or (ii) automatically upon the approval by the Company’s stockholders of the Reverse Stock Split at any meeting of the stockholders held for the purpose of voting on such proposal. Each share of Series K Preferred Stock redeemed in any redemption described above will be redeemed in consideration for the right to receive an amount equal to $0.10 in cash for each one hundred whole shares of Series K Preferred Stock that are “beneficially owned” by the “beneficial owner” (as such terms are defined in the certificate of designation with respect to the Series K Preferred Stock (the “Series K Certificate of Designation”)) thereof as of the applicable redemption time and redeemed pursuant to such redemption, payable upon receipt by the Company of a written request submitted by the applicable holder to the corporate secretary of the Company (each a “Redemption Payment Request”) following the applicable redemption time. Such Redemption Payment Request shall (i) be in a form reasonably acceptable to the Company (ii) set forth in reasonable detail the number of shares of Series K Preferred Stock beneficially owned by the holder at the applicable redemption time and include evidence reasonably satisfactory to the Company regarding the same, and (iii) set forth a calculation specifying the amount in cash owed to such Holder by the Company with respect to the shares of Series K Preferred Stock that were redeemed at the applicable redemption time. However, the redemption consideration in respect of the shares of Series K Preferred Stock (or fractions thereof) redeemed in any redemption described above: (i) will entitle the former beneficial owners of less than one hundred whole shares of Series K Preferred Stock redeemed in any redemption to no cash payment in respect thereof and (y) will, in the case of a former beneficial owner of a number of shares of Series K Preferred Stock (or fractions thereof) redeemed pursuant to any redemption that is not equal to a whole number that is a multiple of one hundred, entitle such beneficial owner to the same cash payment, if any, in respect of such redemption as would have been payable in such redemption to such beneficial owner if the number of shares (or fractions thereof) beneficially owned by such beneficial owner and redeemed pursuant to such redemption were rounded down to the nearest whole number that is a multiple of one hundred (such, that for example, the former beneficial owner of 150 shares of Series K Preferred Stock redeemed pursuant to any redemption will be entitled to receive the same cash payment in respect of such redemption as would have been payable to the former beneficial owner of 100 shares of Series K Preferred Stock redeemed pursuant to such redemption). The Series K Preferred Stock is not convertible into, or exchangeable for, shares of any other class or series of stock or other securities of the Company. The Series K Preferred Stock has no stated maturity and is not subject to any sinking fund. The Series K Preferred Stock is not subject to any restriction on the redemption or repurchase of shares by the Company while there is any arrearage in the payment of dividends or sinking fund installments. The Series K Certificate of Designation was filed with the Delaware Secretary of State and became effective on June 16, 2023. On June 27, 2023, the Company issued 83,949 shares of Series K Preferred Stock to the holders of the Company’s Common Stock. Partial Term Note Exchange On June 29, 2023, the Company entered into a letter agreement with John K. Scott, Jr. to exchange $1,073,600 principal amount of the 2022 Bridge Note for 12,200,000 shares of Common Stock based on the closing stock price on June 28, 2023. See Note 8.

Note 12 - Stock Warrants

Note 12 - Stock Warrants	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Stock Warrants Disclosure [Text Block]	12. Stock Warrants As of June 30, 2023, there are 23,348,906 warrants outstanding to purchase Navidea's Common Stock. The warrants are exercisable at prices ranging from $0.16 to $0.94 per share with a weighted average exercise price of $0.17 per share. The warrants have remaining outstanding terms ranging from 1.0 to 4.2 years.

Note 13- Income Taxes

Note 13- Income Taxes	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Income Tax Disclosure [Text Block]	13. Income Taxes Income taxes are accounted for under the asset and liability method in accordance with Accounting Standards Codification 740, Income Taxes Current accounting standards require a valuation allowance against DTAs if, based on the weight of available evidence, it is more likely than not that some or all of the DTAs may not be realized. Due to the uncertainty surrounding the realization of these DTAs in future tax returns, all of the DTAs have been fully offset by a valuation allowance as of June 30, 2023 and December 31, 2022. In assessing the realizability of DTAs, management considers whether it is more likely than not that some portion or all of the DTAs will not be realized. The ultimate realization of DTAs is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities (including the impact of available carryback and carryforward periods) and projected future taxable income in making this assessment. Based upon the level of historical taxable income and projections for future taxable income over the periods in which the DTAs are deductible, management believes it is more likely than not that the Company will not realize the benefits of these deductible differences or tax carryforwards as of June 30, 2023. Current accounting standards include guidance on the accounting for uncertainty in income taxes recognized in the financial statements. Such standards also prescribe a recognition threshold and measurement model for the financial statement recognition of a tax position taken, or expected to be taken, and provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, disclosure and transition. The Company believes that the ultimate deductibility of all tax positions is highly certain, although there is uncertainty about the timing of such deductibility. As a result, no liability for uncertain tax positions was recorded as of June 30, 2023 or December 31, 2022 and we do not expect any significant changes in the next twelve months. Should we need to accrue interest or penalties on uncertain tax positions, we would recognize the interest as interest expense and the penalties as a selling, general and administrative expense. As of June 30, 2023, tax years 2019-2022 remained subject to examination by federal and state tax authorities. As of June 30, 2023, we had approximately $175.1 million of federal and $20.1 million of state net operating loss carryforwards, as well as approximately $8.9 million of federal R&D credit carryforwards which expire from 2023 to 2040.

Note 14 - Segments

Note 14 - Segments	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Segment Reporting Disclosure [Text Block]	14. Segments We report information about our operating segments using the “management approach” in accordance with current accounting standards. This information is based on the way management organizes and reports the segments within the enterprise for making operating decisions and assessing performance. Our reportable segments are identified based on differences in products, services and markets served. There were no inter-segment sales. We manage our business based on two primary types of drug products: (i) diagnostic substances, including Tc99m tilmanocept and other diagnostic applications of our Manocept platform, and (ii) therapeutic development programs, including therapeutic applications of our Manocept platform. The information in the following tables is derived directly from each reportable segment’s financial reporting. Three Months Ended June 30, 2023 Diagnostics Therapeutics Corporate Total Research and development expenses $ 1,057,046 $ 49,219 $ — $ 1,106,265 Selling, general and administrative expenses, excluding depreciation and amortization (1) — 882 1,293,416 1,294,298 Depreciation and amortization (2) 9,527 — 17,608 27,135 Loss from operations (3) (1,066,573 ) (50,101 ) (1,311,024 ) (2,427,698 ) Other income, net (4) — — 1,034,514 1,034,514 Loss from continuing operations (1,066,573 ) (50,101 ) (276,510 ) (1,393,184 ) Total assets, net of depreciation and amortization: United States $ — $ — $ 7,638,388 $ 7,638,388 International 568,856 — 12,568 581,424 Three Months Ended June 30, 2022 Diagnostics Therapeutics Corporate Total Sales revenue: International $ 6,519 $ — $ — $ 6,519 Grant and other revenue 51,007 — — 51,007 Total revenue 57,526 — — 57,526 Cost of revenue, excluding depreciation and amortization 473 — — 473 Research and development expenses 1,636,691 87,297 — 1,723,988 Selling, general and administrative expenses, excluding depreciation and amortization (1) — 3,001 1,230,894 1,233,895 Depreciation and amortization (2) 6,041 — 15,730 21,771 Loss from operations (3) (1,585,679 ) (90,298 ) (1,246,624 ) (2,922,601 ) Other expense, net (4) — — (76,858 ) (76,858 ) Net loss (1,585,679 ) (90,298 ) (1,323,482 ) (2,999,459 ) Total assets, net of depreciation and amortization: United States $ 50,000 $ — $ 2,043,815 $ 2,093,815 International 384,294 — 25,596 409,890 Capital expenditures 40,221 — 8,436 48,657 Six Months Ended June 30, 2023 Diagnostics Therapeutics Corporate Total Research and development expenses $ 2,227,599 $ 146,119 $ — $ 2,373,718 Selling, general and administrative expenses, excluding depreciation and amortization (1) — 3,060 2,418,599 2,421,659 Depreciation and amortization (2) 18,802 — 35,888 54,690 Loss from operations (3) (2,246,401 ) (149,179 ) (2,454,487 ) (4,850,067 ) Other income, net (4) — — 1,980,553 1,980,553 Loss from continuing operations (2,246,401 ) (149,179 ) (473,934 ) (2,869,514 ) Total assets, net of depreciation and amortization: United States $ — $ — $ 7,638,388 $ 7,638,388 International 568,856 — 12,568 581,424 Capital expenditures 15,068 — — 15,068 Six Months Ended June 30, 2022 Diagnostics Therapeutics Corporate Total Sales revenue: International $ 6,519 $ — $ — $ 6,519 Grant and other revenue 51,007 — — 51,007 Total revenue 57,526 — — 57,526 Cost of revenue, excluding depreciation and amortization 473 — — 473 Research and development expenses 2,626,578 266,664 — 2,893,242 Selling, general and administrative expenses, excluding depreciation and amortization (1) — 3,001 3,018,045 3,021,046 Depreciation and amortization (2) 12,081 — 32,568 44,649 Loss from operations (3) (2,581,606 ) (269,665 ) (3,050,613 ) (5,901,884 ) Other expense, net (4) — — (84,819 ) (84,819 ) Net loss (2,581,606 ) (269,665 ) (3,135,432 ) (5,986,703 ) Total assets, net of depreciation and amortization: United States $ 50,000 $ — $ 2,043,815 $ 2,093,815 International 384,294 — 25,596 409,890 Capital expenditures 40,221 — 8,436 48,657 (1) General and administrative expenses, excluding depreciation and amortization, represent costs that relate to the general administration of the Company and as such are not currently allocated to our individual reportable segments, other than those expenses directly incurred by Navidea Europe, Navidea UK and MT. (2) Depreciation and amortization are reflected in selling, general and administrative expenses ($27,135 (3) Loss from operations does not reflect the allocation of certain selling, general and administrative expenses, excluding depreciation and amortization, to our individual reportable segments, other than those expenses directly incurred by Navidea Europe, Navidea UK and MT. (4) Amounts consist primarily of gain on contract amendment, gain on sale of non-financial asset, loss on debt extinguishment, adjustment of accrued interest, interest income and interest expense, which are not currently allocated to our individual reportable segments.

Note 15 - Supplemental Disclosu

Note 15 - Supplemental Disclosure for Statements of Cash Flows	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Cash Flow, Supplemental Disclosures [Text Block]	15. Supplemental Disclosure for Statements of Cash Flows During the six-month periods ended June 30, 2023 and 2022, we paid interest aggregating $98,201 and $31,126, respectively. During the six-month periods ended June 30, 2023 and 2022, we issued 163,586 and 53,238 shares of our Common Stock as matching contributions to our 401(k) Plan, which were valued at $52,348 and $44,720, respectively. During the six-month period ended June 30, 2022, we issued 16,632 shares of our Common Stock to certain of our employees as partial payment in lieu of cash for their 2021 bonuses, which were valued at $16,965. During the six-month period ended June 30, 2023, we issued 200,000 shares of our Common Stock as commitment shares to Keystone under the Purchase Agreement, which were valued at $50,000. During the six-month period ended June 30, 2023, the Company recorded additional paid-in capital of $1,061,400 related to Mr. Scott’s partial exchange of the 2022 Bridge Note for 12,200,000 shares of Common Stock. During the six-month period ended June 30, 2023, the Company recorded a deemed dividend of $138,045 related to the exchange of Series G Preferred Stock and accrued dividends thereon for Series J Preferred Stock. During the six-month period ended June 30, 2023, we obtained right-of-use lease assets in exchange for new operating lease liabilities of $17,503. During the six-month period ended June 30, 2023, 5,335 shares of Series I Preferred Stock were converted into 33,277,222 shares of Common Stock. During the six-month period ended June 30, 2023, 11,969 shares of Series J Preferred Stock were converted into 11,508,672 shares of Common Stock.

Note 16 - Discontinued Operatio

Note 16 - Discontinued Operations	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]	16. Discontinued Operations On March 3, 2017, the Company completed the sale to Cardinal Health of its assets used, held for use, or intended to be used in operating its business of developing, manufacturing and commercializing a product used for lymphatic mapping, lymph node biopsy, and the diagnosis of metastatic spread to lymph nodes for staging of cancer, including the Company’s radioactive diagnostic agent marketed under the Lymphoseek® trademark for current approved indications by the FDA and similar indications approved by the FDA in the future (the “Acquired Assets”), in Canada, Mexico and the United States. In exchange for the Acquired Assets, Cardinal Health (i) made a cash payment to the Company at closing of approximately $80.6 million after adjustments based on inventory being transferred and an advance of $3.0 million of guaranteed earnout payments as part of the CRG settlement, (ii) assumed certain liabilities of the Company associated with the Product as specified in the Asset Purchase Agreement, and (iii) agreed to make periodic earnout payments (to consist of contingent payments and milestone payments which, if paid, will be treated as additions to the purchase price) to the Company based on net sales derived from the purchased Product. On April 2, 2018, the Company entered into an Amendment to the Asset Purchase Agreement (the “First Amendment”). Pursuant to the First Amendment, Cardinal Health paid the Company approximately $6.0 million and agreed to pay the Company an amount equal to the unused portion of the letter of credit in favor of CRG (not to exceed approximately $7.1 million) promptly after the earlier of (i) the expiration of the letter of credit and (ii) the receipt by Cardinal Health of evidence of the return and cancellation of the letter of credit. In exchange, the obligation of Cardinal Health to make any further contingent payments has been eliminated. Cardinal Health is still obligated to make the milestone payments in accordance with the terms of the earnout provisions of the Purchase Agreement. On April 9, 2018, CRG drew approximately $7.1 million on the letter of credit. On June 14, 2023, the Company entered into a Second Amendment to Asset Purchase Agreement (the “Second Amendment”) with Cardinal Health, in respect of that certain Asset Purchase Agreement, dated November 23, 2016, by and between the Cardinal Health and the Company. Under the Second Amendment, Cardinal Health paid to the Company a lump sum payment of $7.5 million in cash in consideration of certain amendments to the Asset Purchase Agreement, including elimination of Cardinal Health’s obligation to pay a certain milestone payment to the Company. During the second quarter of 2023, we recorded a net gain related to the Second Amendment of $7.4 million in the condensed consolidated statement of operations. There were no

Note 17 - Subsequent Events

Note 17 - Subsequent Events	6 Months Ended
	Jun. 30, 2023
Notes to Financial Statements
Subsequent Events [Text Block]	17. Subsequent Events The Company has evaluated events and transactions subsequent to June 30, 2023 and through the date these condensed consolidated financial statements were included in this Quarterly Report on Form 10-Q and filed with the SEC. On July 28, 2023, the Company received written notification from NYSE American stating that the staff of NYSE Regulation has determined to commence proceedings to delist the Company’s Common Stock. NYSE Regulation has determined that the Company is no longer suitable for listing pursuant to Section 1009(a) of the NYSE American Company Guide as the Company was unable to demonstrate that it had regained compliance with Sections 1003(a)(i), (ii) and (iii) of the NYSE American Company Guide by the end of the maximum 18-month compliance plan period, which expired on July 28, 2023. The NYSE American’s application with the SEC to delist the Company’s Common Stock is pending, subject to completion of all applicable procedures, including any appeal by the Company of the NYSE Regulation staff’s decision. On August 4, 2023, the Company filed a written request to appeal the NYSE Regulation staff’s decision. There can be no assurance that the Company’s request for continued listing will be granted. The Company’s Common Stock will continue to be listed and traded on NYSE American during the pendency of the Company’s appeal, subject to NYSE American’s discretion to immediately suspend trading if it believes suspension to be in the public interest, for the protection of investors, or to promote just and equitable principles of trade.

Note 3 - Revenue From Contrac_2

Note 3 - Revenue From Contracts With Customers and Other Revenue (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Disaggregation of Revenue [Table Text Block]	Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Sales revenue: Tc99m tilmanocept - Europe $ — $ 6,519 $ — $ 6,519
Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]	June 30, 2023 December 31, 2022 (unaudited) Total deferred revenue related to contracts with customers, beginning of period $ 700,000 $ 700,000 Total deferred revenue, end of period $ 700,000 $ 700,000

Note 4 - Stock-based Compensa_2

Note 4 - Stock-based Compensation (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Share-Based Payment Arrangement, Option, Activity [Table Text Block]	Six Months Ended June 30, 2023 Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value Outstanding, January 1, 2023 702,805 $ 4.42 5.5 $ — Granted 1,339,500 0.32 Cancelled/Forfeited (966,465 ) 0.76 Expired (850 ) 61.60 Outstanding, June 30, 2023 1,074,990 $ 2.55 7.1 $ — Exercisable, June 30, 2023 461,115 $ 5.48 3.6 $ —
Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]	Six Months Ended June 30, 2023 Number of Shares Weighted Average Grant-Date Fair Value Unvested, January 1, 2023 90,000 $ 0.99 Vested — — Unvested, June 30, 2023 90,000 $ 0.99

Note 6 - Inventory, Net (Tables

Note 6 - Inventory, Net (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Inventory, Current [Table Text Block]	June 30, 2023 December 31, 2022 Materials $ 27,405 $ 27,405 Work in process 433,341 399,939 Finished goods 131,804 131,804 Reserve for expiring finished goods (131,804 ) (131,804 ) Total inventory, net $ 460,746 $ 427,344

Note 9 - Leases (Tables)

Note 9 - Leases (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]	Maturity of Lease Liabilities Operating Lease Payments 2023 (remaining) $ 18,886 2024 1,355 Total undiscounted operating lease payments 20,241 Less imputed interest (677 ) Present value of operating lease liabilities $ 19,564
Lessee, Operating Lease, Assets and Liabilities [Table Text Block]	Balance Sheet Classification Current lease liabilities $ 19,030 Noncurrent lease liabilities 534 Total operating lease liabilities $ 19,564
Lessee, Leases, Other Information [Table Text Block]	Other Information Weighted-average remaining lease term for operating leases (in years) 0.6 Weighted-average discount rate for operating leases 10.67 %

Note 14 - Segments (Tables)

Note 14 - Segments (Tables)	6 Months Ended
	Jun. 30, 2023
Notes Tables
Schedule of Segment Reporting Information, by Segment [Table Text Block]	Three Months Ended June 30, 2023 Diagnostics Therapeutics Corporate Total Research and development expenses $ 1,057,046 $ 49,219 $ — $ 1,106,265 Selling, general and administrative expenses, excluding depreciation and amortization (1) — 882 1,293,416 1,294,298 Depreciation and amortization (2) 9,527 — 17,608 27,135 Loss from operations (3) (1,066,573 ) (50,101 ) (1,311,024 ) (2,427,698 ) Other income, net (4) — — 1,034,514 1,034,514 Loss from continuing operations (1,066,573 ) (50,101 ) (276,510 ) (1,393,184 ) Total assets, net of depreciation and amortization: United States $ — $ — $ 7,638,388 $ 7,638,388 International 568,856 — 12,568 581,424 Three Months Ended June 30, 2022 Diagnostics Therapeutics Corporate Total Sales revenue: International $ 6,519 $ — $ — $ 6,519 Grant and other revenue 51,007 — — 51,007 Total revenue 57,526 — — 57,526 Cost of revenue, excluding depreciation and amortization 473 — — 473 Research and development expenses 1,636,691 87,297 — 1,723,988 Selling, general and administrative expenses, excluding depreciation and amortization (1) — 3,001 1,230,894 1,233,895 Depreciation and amortization (2) 6,041 — 15,730 21,771 Loss from operations (3) (1,585,679 ) (90,298 ) (1,246,624 ) (2,922,601 ) Other expense, net (4) — — (76,858 ) (76,858 ) Net loss (1,585,679 ) (90,298 ) (1,323,482 ) (2,999,459 ) Total assets, net of depreciation and amortization: United States $ 50,000 $ — $ 2,043,815 $ 2,093,815 International 384,294 — 25,596 409,890 Capital expenditures 40,221 — 8,436 48,657 Six Months Ended June 30, 2023 Diagnostics Therapeutics Corporate Total Research and development expenses $ 2,227,599 $ 146,119 $ — $ 2,373,718 Selling, general and administrative expenses, excluding depreciation and amortization (1) — 3,060 2,418,599 2,421,659 Depreciation and amortization (2) 18,802 — 35,888 54,690 Loss from operations (3) (2,246,401 ) (149,179 ) (2,454,487 ) (4,850,067 ) Other income, net (4) — — 1,980,553 1,980,553 Loss from continuing operations (2,246,401 ) (149,179 ) (473,934 ) (2,869,514 ) Total assets, net of depreciation and amortization: United States $ — $ — $ 7,638,388 $ 7,638,388 International 568,856 — 12,568 581,424 Capital expenditures 15,068 — — 15,068 Six Months Ended June 30, 2022 Diagnostics Therapeutics Corporate Total Sales revenue: International $ 6,519 $ — $ — $ 6,519 Grant and other revenue 51,007 — — 51,007 Total revenue 57,526 — — 57,526 Cost of revenue, excluding depreciation and amortization 473 — — 473 Research and development expenses 2,626,578 266,664 — 2,893,242 Selling, general and administrative expenses, excluding depreciation and amortization (1) — 3,001 3,018,045 3,021,046 Depreciation and amortization (2) 12,081 — 32,568 44,649 Loss from operations (3) (2,581,606 ) (269,665 ) (3,050,613 ) (5,901,884 ) Other expense, net (4) — — (84,819 ) (84,819 ) Net loss (2,581,606 ) (269,665 ) (3,135,432 ) (5,986,703 ) Total assets, net of depreciation and amortization: United States $ 50,000 $ — $ 2,043,815 $ 2,093,815 International 384,294 — 25,596 409,890 Capital expenditures 40,221 — 8,436 48,657

Note 1 - Summary of Significa_2

Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($)	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Patent and Trademark Costs	$ 89,678	$ 190,727
Previously Capitalized Patent Costs Abandoned	$ 1,376	$ 62,388
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life	5 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	15 years

Note 2 - Liquidity (Details Tex

Note 2 - Liquidity (Details Textual) - USD ($)	Apr. 10, 2023	Aug. 30, 2022	Aug. 11, 2022	Jun. 30, 2023	Mar. 31, 2023	Oct. 11, 2022	Sep. 30, 2022
The Business [Member]
Proceeds from Divestiture of Businesses	$ 250,000
Disposal Group, Including Discontinued Operation, Consideration Receivable Within 60 Days After Closing Date	$ 500,000
API Development Funding and Access Agreement [Member]
Development Agreement, Reimbursement Amount				$ 1,850,000
Development Agreement, Reimbursement Proceeds			$ 800,000
CRG Loan Agreement, Texas Case [Member]
Litigation Settlement, Amount Awarded to Other Party		$ 2,600,000
Loss Contingencies, Interest Rate				5%	18%	5%	18%
Loss Contingency Accrual				$ 2,679,380

Note 3 - Revenue From Contrac_3

Note 3 - Revenue From Contracts With Customers and Other Revenue (Details Textual) - USD ($)		3 Months Ended		6 Months Ended		18 Months Ended
	Aug. 11, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Dec. 31, 2022
Contract with Customer, Payment Term, Minimum				15 days
Contract with Customer, Payment Term, Maximum (Day)				90 days
Contract with Customer, Transaction Price of Royalties Using Expected Value Method		$ 0		$ 0		$ 0
Revenue from Contract with Customer, Including Assessed Tax		0	$ 6,519	0	$ 6,519	6,519
Contract with Customer, Asset, Impairment Loss		0	0	0	0
Capitalized Contract Cost, Net, Total		0		0		0
API Development Funding and Access Agreement [Member]
Development Agreement, Reimbursement Amount		1,850,000		1,850,000		1,850,000
Development Agreement, Reimbursement Proceeds	$ 800,000
Sales Revenue [Member]
Contract with Customer, Asset, after Allowance for Credit Loss		0		0		0	$ 610
License [Member]
Contract with Customer, Asset, after Allowance for Credit Loss		0		0		$ 0	$ 0
Grant [Member]
Revenue Not from Contract with Customer		$ 0	$ 51,007	$ 0	$ 51,007
INDIA
Contract with Customer, Term of Contract (Year)				8 years
CHINA
Contract with Customer, Term of Contract (Year)				10 years

Note 3 - Revenue From Contrac_4

Note 3 - Revenue From Contracts With Customers and Other Revenue - Disaggregation of Revenue (Details) - USD ($)	3 Months Ended		6 Months Ended		18 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023
Revenue from contract with customer	$ 0	$ 6,519	$ 0	$ 6,519	$ 6,519
Diagnostics Segment [Member] | Europe [Member] | Sales Revenue [Member]
Revenue from contract with customer	$ 0	$ 6,519	$ 0	$ 6,519

Note 3 - Revenue From Contrac_5

Note 3 - Revenue From Contracts With Customers and Other Revenue - Changes in Contract Liabilities (Details) - USD ($)	Jun. 30, 2023	Jun. 29, 2023	Dec. 31, 2022
Total deferred revenue related to contracts with customers, beginning of period	$ 700,000	$ 700,000	$ 700,000
Total deferred revenue, end of period	$ 700,000	$ 700,000	$ 700,000

Note 4 - Stock-based Compensa_3

Note 4 - Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Allocated Share-based Compensation Expense (Reversal)	$ (33,841)	$ 40,555	$ (14,172)	$ 225,405
Share-Based Payment Arrangement, Expense, Tax Benefit	0	$ 0	$ 0	$ 0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 0.24
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum			89.47%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			3.87%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term			5 years 11 months 12 days
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 150,429		$ 150,429
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			1 year 8 months 19 days

Note 4 - Stock-based Compensa_4

Note 4 - Stock-based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Outstanding, options (in shares)	702,805
Outstanding, weighted average exercise price (in dollars per share)	$ 4.42
Outstanding, weighted average remaining contractual life (Year)	7 years 1 month 6 days	5 years 6 months
Outstanding, aggregate intrinsic value	$ 0	$ 0
Granted, options (in shares)	1,339,500
Granted, weighted average exercise price (in dollars per share)	$ 0.32
Cancelled/Forfeited, options (in shares)	(966,465)
Cancelled/Forfeited, weighted average exercise price (in dollars per share)	$ 0.76
Expired, options (in shares)	(850)
Expired, weighted average exercise price (in dollars per share)	$ 61.60
Outstanding, options (in shares)	1,074,990	702,805
Outstanding, weighted average exercise price (in dollars per share)	$ 2.55	$ 4.42
Exercisable, options (in shares)	461,115
Exercisable, weighted average exercise price (in dollars per share)	$ 5.48
Exercisable, weighted average remaining contractual life (Year)	3 years 7 months 6 days
Exercisable, aggregate intrinsic value	$ 0

Note 4 - Stock-based Compensa_5

Note 4 - Stock-based Compensation - Summary of Unvested Restricted Stock (Details) - Restricted Stock [Member]	6 Months Ended
	Jun. 30, 2023 $ / shares shares
Unvested, shares (in shares) | shares	90,000
Unvested, weighted average grant-date fair value (in dollars per share) | $ / shares	$ 0.99
Vested, shares (in shares) | shares	0
Vested, weighted average grant-date fair value (in dollars per share) | $ / shares	$ 0
Unvested, shares (in shares) | shares	90,000
Unvested, weighted average grant-date fair value (in dollars per share) | $ / shares	$ 0.99

Note 5 - Earnings (Loss) Per _2

Note 5 - Earnings (Loss) Per Share (Details Textual) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Stock Options and Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	24,423,896	1,148,404
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	90,000	90,000

Note 6 - Inventory, Net (Detail

Note 6 - Inventory, Net (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Finished Goods [Member]
Inventory, Allocated to Research and Development Expense	$ 0	$ 0	$ 0	$ 0

Note 6 - Inventory, Net - Net I

Note 6 - Inventory, Net - Net Inventory (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Materials	$ 27,405	$ 27,405
Work in process	433,341	399,939
Finished goods	131,804	131,804
Reserve for expiring finished goods	(131,804)	(131,804)
Total inventory, net	$ 460,746	$ 427,344

Note 7 - Accounts Payable, Ac_2

Note 7 - Accounts Payable, Accrued Liabilities and Other (Details Textual) - USD ($)		6 Months Ended
	Mar. 30, 2023	Jun. 30, 2023	Apr. 13, 2023	Dec. 31, 2022
Accrued liabilities and other		$ 4,159,946		$ 6,456,762
UCSD [Member]
License Agreement Fees		259,000
Accruals Reversed Due to Amendment		1,200,000
Account Payable [Member] | UCSD [Member]
License Agreement Fees		104,000
Accrued Liabilities and Other [Member] | UCSD [Member]
License Agreement Fees		155,000
Director Fees [Member] | Account Payable [Member]
Accounts Payable		464,986		318,527
Termination Costs, Bonuses, and Benefits [Member] | Accrued Liabilities and Other [Member]
Accrued liabilities and other		$ 438,657		$ 811,544
Separation Agreement [Member] | Former Chief Medical Officer [Member]
Lump Sum Payment Payable, Net			$ 25,000
Separation Agreement, Payment, Per Hour Rate	$ 300
Consulting Agreement [Member] | G2G Ventures [Member]
Monthly Retainer Amount	$ 50,000

Note 8 - Notes Payable (Details

Note 8 - Notes Payable (Details Textual)						1 Months Ended		3 Months Ended		6 Months Ended		18 Months Ended
	Jun. 29, 2023 USD ($) shares	May 09, 2023 AED (د.إ)	Apr. 26, 2023 USD ($)	Jul. 01, 2022 USD ($)	Apr. 10, 2022 USD ($) shares	Nov. 30, 2022 USD ($)	Nov. 30, 2021 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Apr. 25, 2023 USD ($)	Apr. 24, 2023 USD ($)	Dec. 31, 2022 USD ($)
Difference Betweent Value of Conversion Stocks					$ 821,250
Gain (Loss) on Extinguishment of Debt								$ (185,056)	$ 0	$ (185,056)	$ 0
Interest Expense, Debt								160,716	83,596	312,229	87,308
Notes Payable, Current								1,319,105		1,319,105		$ 1,319,105			$ 543,613
Long-Term Debt, Maturity, Year One								138,573		138,573		138,573
Long-Term Debt, Maturity, Year Two								1,430,000		1,430,000		1,430,000
AFCO Premium Credit LLC [Member]
Interest Expense, Debt										14,763	$ 0
Bridge Note 2022 Converted to Common Stock [Member]
Debt Conversion, Converted Instrument, Shares Issued | shares	12,200,000
The 2023 Bridge Note [Member] | Vice Chairman of Board of Directors [Member]
Proceeds from Issuance of Long-Term Debt		د.إ 75,000	$ 225,000
The 2023 Bridge Note [Member] | Vice Chairman of Board of Directors [Member] | Maximum [Member]
Debt Instrument, Face Amount														$ 300,000
Bridge Note 2023 [Member]
Debt Instrument, Face Amount													$ 300,000
Debt Instrument, Fee Amount													15,000
Interest Payable													$ 105
Interest Expense, Debt										105
Long-Term Debt								0		0		0
Bridge Note 2022 [Member]
Debt Instrument, Face Amount	$ 1,073,600
Extinguishment of Debt, Amount	$ 185,056
Gain (Loss) on Extinguishment of Debt								(185,056)
Notes Payable Issued for Prepayment of Insurance Premiums [Member]
Interest Expense, Debt										0		4,126,000
Notes Payable Issued for Prepayment of Insurance Premiums [Member] | IPFS [Member]
Debt Instrument, Face Amount							$ 565,760
Debt Instrument, Interest Rate, Stated Percentage							4.36%
Interest Expense, Debt								0	414
Debt Instrument, Term							5 months
Debt Instrument, Periodic Payment							$ 114,388
Notes Payable, Current								0		0		0
Series E Preferred Stock Exchanged for Sereis F and G Preferred Stock [Member]
Conversion of Stock, Shares Converted | shares					50,000
Series E Preferred Stock Exchanged for Sereis F Preferred Stock [Member]
Conversion of Stock, Shares Issued | shares					1,740
Series E Preferred Stock Exchanged for Sereis G Preferred Stock [Member]
Conversion of Stock, Shares Issued | shares					3,260
Bridge Loan [Member]
Debt Instrument, Face Amount					$ 2,500,000
Proceeds from Issuance of Long-Term Debt				$ 1,000,000	$ 1,500,000
Debt Instrument, Interest Rate, Stated Percentage					8%
Debt Instrument, Unamortized Discount					$ 835,876
Debt Issuance Costs, Net					$ 14,626
Interest Expense, Debt								155,210
Long-Term Debt								1,426,400		1,426,400		1,426,400
Bridge Loan
Debt Instrument, Unamortized Discount								245,868		245,868		245,868
Interest Expense, Debt										297,361
Notes Payable Issued for Prepayment of Insurance Premiums [Member] | AFCO Premium Credit LLC [Member]
Debt Instrument, Face Amount						$ 608,275
Debt Instrument, Interest Rate, Stated Percentage						7.85%
Interest Expense, Debt								5,401	$ 0
Long-Term Debt								$ 138,573		$ 138,573		$ 138,573
Debt Instrument, Periodic Payment						$ 69,967

Note 9 - Leases (Details Textua

Note 9 - Leases (Details Textual)	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2023 USD ($) ft²	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) ft²	Jun. 30, 2022 USD ($)
Operating Lease, Expense				$ 18,897	$ 73,173
Operating Lease, Payments				$ 18,886	$ 187,779
Selling, General and Administrative Expenses [Member]
Operating Lease, Expense		$ 9,449	$ 35,497
Office Space at 4995 Bradenton Avenue, Dublin Ohio [Member]
Area of Real Estate Property | ft²		5,000		5,000
Operating Lease, Monthly Base Rent				$ 3,012
Office Space at 5600 Blazer Parkway, Dublin, Ohio [Member]
Area of Real Estate Property | ft²		25,000		25,000
Operating Lease, Monthly Base Rent	$ 39,124			$ 28,149
Office Equipment [Member]
Operating Lease, Monthly Base Rent				$ 136

Note 9 - Leases - Maturity of L

Note 9 - Leases - Maturity of Lease Liabilities (Details)	Jun. 30, 2023 USD ($)
2023 (remaining)	$ 18,886
2024	1,355
Total undiscounted operating lease payments	20,241
Less imputed interest	677
Present value of operating lease liabilities	$ 19,564

Note 9 - Leases - Balance Sheet

Note 9 - Leases - Balance Sheet Classification (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Current lease liabilities	$ 19,030	$ 18,976
Noncurrent lease liabilities	534	$ 1,312
Present value of operating lease liabilities	19,564
Other Current Liabilities [Member]
Current lease liabilities	19,030
Other Noncurrent Liabilities [Member]
Noncurrent lease liabilities	$ 534

Note 9 - Leases - Other Informa

Note 9 - Leases - Other Information (Details)	Jun. 30, 2023
Weighted-average remaining lease term for operating leases (in years) (Year)	7 months 6 days
Weighted-average discount rate for operating leases	10.67%

Note 10 - Commitments and Con_2

Note 10 - Commitments and Contingencies (Details Textual) - USD ($)								1 Months Ended		3 Months Ended
	Mar. 15, 2023	Aug. 30, 2022	Apr. 08, 2022	Nov. 21, 2021	May 27, 2021	Apr. 09, 2018	Mar. 03, 2017	Nov. 30, 2018	Jun. 30, 2016	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Oct. 11, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Aug. 14, 2018
Equity, Including Portion Attributable to Noncontrolling Interest										$ (786,584)	$ (9,547,623)	$ (8,143,310)			$ (4,240,647)	$ (2,109,442)	$ 624,743
Common Stock [Member]
Stock Issued During Period, Shares, New Issues										6,308,489
Equity, Including Portion Attributable to Noncontrolling Interest										$ 287,146	$ 223,848	$ 223,684			$ 221,361	$ 221,354	$ 221,277
Former Chief Executive Officer and President [Member]
Common Stock Shares Provided by Agreement																		1,175,000
Former Chief Executive Officer and President [Member] | Common Stock [Member]
Stock Issued During Period, Shares, New Issues								925,000
Stock Issued During Period, Shares, New Issues Placed in Escrow								250,000
Former Chief Executive Officer and President [Member] | Dr. Michael Goldberg [Member] | MT [Member] | Common Stock [Member]
Ownership Percentage																		5%
CRG [Member]
Draws on Letter of Credit						$ 7,153,000
CRG Loan Agreement, Texas Case [Member]
Litigation Settlement, Attorneys’ Fees				$ 2,800,000
Litigation Settlement, Amount Awarded to Other Party		$ 2,600,000
Post Judgement Interest Rate										5%
Loss Contingencies, Interest Rate										5%	18%		5%	18%
Interest Payable										$ 771,000
Loss Contingency Accrual										$ 2,679,380
CRG Loan Agreement, Texas Case [Member] | Judicial Ruling [Member]
Loss Contingency, Damages Awarded, Value, Additional Amount							$ 7,000,000
Loss Contingency, Damages Awarded, Value, Amount not Taken into Consideration						$ 4,200,000			$ 4,100,000
New York Litigation Involving Former CEO and President [Member] | Judicial Ruling [Member]
Litigation Settlement, Amount Awarded to Other Party	$ 12,600
Litigation Settlement, Amount Can Be Awarded to Other Party for Indemnification for Attorneys’ Fees					$ 14,955
Litigation Settlement, Amount Can Be Advanced to Other Party for Attorneys’ Fees Subject to Repayment					$ 1,237
Litigation Settlement, Advancement for Attorney's Fees and Disbursements			$ 143,172
CRG [Member] | Term Loan Agreement [Member] | CRG Loan Agreement, Texas Case [Member] | Judicial Ruling [Member]
Repayments of Debt							59,000,000
CRG [Member] | Term Loan Agreement [Member] | Maximum [Member]
Debt Instrument, Agreed-upon Final Payoff Amount							$ 66,000,000

Note 11 - Equity (Details Textu

Note 11 - Equity (Details Textual)										1 Months Ended	3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 29, 2023 USD ($) shares	Jun. 27, 2023 shares	Jun. 06, 2023 shares	Jun. 01, 2023 USD ($) shares	May 22, 2023 USD ($) $ / shares shares	Apr. 26, 2023 USD ($) shares	Mar. 10, 2023 $ / shares shares	Sep. 09, 2022	Apr. 07, 2022 shares	May 25, 2023 USD ($) $ / shares shares	Jun. 30, 2023 USD ($) $ / shares shares	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2022 USD ($) shares	Dec. 31, 2022 USD ($) $ / shares shares	Jun. 16, 2023 $ / shares	May 10, 2023 shares	May 02, 2023 shares	Apr. 25, 2023 $ / shares	May 22, 2022 shares
Operating Loss Carryforwards | $																$ 175,000,000
Share Purchase Right, Shares Issuable Per Each Right									0.001
Share Purchase Right, Ownership Percentage Threshold									4.99%
Share Purchase Right, Ownership Percentage Trigger									0.50%
Share Purchase Right, Discount Percentage									50%
Stock Issued During Period, Shares, Employee Benefit Plan (in shares)														163,586	53,238
Stock Issued During Period, Value, Employee Benefit Plan | $												$ 52,348	$ 44,720	$ 52,348	$ 44,720
Stock Issued During Period, Value, New Issues | $											$ 1,089,000
Share Price | $ / shares																				$ 0.25
Proceeds from Issuance of Common Stock | $														$ 643,759	$ 0
Accrued and Unpaid Dividends | $				$ 1,058,853
Conversion of Stock, Amount Issued | $				$ 1,196,900
Common Stock, Par or Stated Value Per Share | $ / shares											$ 0.001			$ 0.001		$ 0.001	$ 0.001
Bridge Note 2022 [Member]
Debt Conversion, Amount Convertible | $	$ 1,073,600
Debt Conversion Shares Issuable	12,200,000
Mr. Scott [Member]
Dividends | $											$ 138,045
Series J Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues					11,000
Shares Issued, Price Per Share | $ / shares					$ 0.001
Aggregative Purchase Price of Preferred Stock | $					$ 1,100,000
Preferred Stock, Shares Authorized											150,000			150,000		150,000					150,000
Issuance Price Divided | $ / shares					$ 0.104
Percentage of Common Stock Outstanding					4.99%
Series G Redeemable Preferred Stock [Member]
Preferred Stock Surrender Shares				990
Accrued and Unpaid Dividends | $				$ 68,853
Series G Preferred Stock [Member]
Preferred Stock, Shares Authorized											3,260			3,260		3,260
Dividends | $											$ 68,853
Number of Shares Surrender											2,270			2,270
Series K Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues		83,949
Shares Issued, Price Per Share | $ / shares											$ 0.001			$ 0.001
Preferred Stock, Shares Authorized											150,000			150,000		150,000
Number of Vote Per Share											1,000,000			1,000,000
Number of Votes Hold											1,000			1,000
Preferred Stock, Redemption Price Per Share (in dollars per share) | $ / shares											$ 0.10			$ 0.10
Preferred Stock, Shares Redeemed											150			150
Number of Shares Benefit Owned											100			100
Conversion of Series I Preferred Stock Into Common Stock [Member]
Preferred Stock, Convertible, Shares Issuable																			6,250
Conversion of Series J preferred Stock Into Common Stock [Member]
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)			11,969											11,969
Accrued and Unpaid Dividends Exchange for Common Stock											27,889			27,889
Conversion of Stock, Shares Issued			11,508,672
Conversion from Series I Preferred Stock To Common Stock [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares										$ 0.16
Purchase Agreement [Member]
Stock Issued During Period, Shares, New Issues										6,108,489
Proceeds from Issuance of Common Stock | $										$ 600,126
Keystone [Member]
Purchase Agreement, Common Stock Shares Issuable																		6,567,409
Percentage of Common Stock Shares Outstanding																		19.99%
Keystone [Member] | Purchase Agreement [Member]
Maximum Amount Shares Issuable | $						$ 2,750,000
Stock Issuable as Consideration for Purchase Commitment						400,000
Stock Issued as Consideration for Purchase Commitment, Delivered Right Away						200,000
Stock Issued as Consideration for Purchase Commitment, Delivered When Milestone Achieved						200,000
Minimum Amount Raised Required for Shares to be Delivered | $						$ 2,750,000
LTIP [Member]
Incentive Plan, Milestone, Percent, Step of Total Stock Award Payout								5%
Incentive Plan, Milestone, Percent, Regulatory Milestones								90%
Incentive Plan, Percent, Milestones Paid																5%
Stock Issued During Period, Shares, New Issues																70,500
Stock Issued During Period, Value, New Issues | $																$ 19,740
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage								100%
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested, Number of Shares							1,339,500
Share-Based Compensation Arrangement by Share-Based Payment Award, Option, Nonvested, Weighted Average Exercise Price | $ / shares							$ 0.32
LTIP [Member] | Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period							10 years

Note 12 - Stock Warrants (Detai

Note 12 - Stock Warrants (Details Textual)	Jun. 30, 2023 $ / shares shares
Class of Warrant or Right, Outstanding | shares	23,348,906
Minimum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.16
Warrants and Rights Outstanding, Term	1 year
Maximum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.94
Warrants and Rights Outstanding, Term	4 years 2 months 12 days
Weighted Average [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.17

Note 13- Income Taxes (Details

Note 13- Income Taxes (Details Textual) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Operating Loss Carryforwards		$ 175
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards	$ 175.1
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount Expired During Period	8.9
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	$ 20.1

Note 14 - Segments (Details Tex

Note 14 - Segments (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Depreciation and amortization (2)	$ 27,135	$ 21,771	$ 54,690	$ 44,649	[1]
[1]Depreciation and amortization are reflected in selling, general and administrative expenses ($27,135

Note 14 - Segments - Segment In

Note 14 - Segments - Segment Information (Details) - USD ($)	3 Months Ended				6 Months Ended			18 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022		Jun. 30, 2023	Dec. 31, 2022
Research and development expenses	$ 1,106,265		$ 1,723,988		$ 2,373,718	$ 2,893,242
Research and development expenses	1,106,265		1,723,988		2,373,718	2,893,242
Revenue from Contract with Customer, Including Assessed Tax	0		6,519		0	6,519		$ 6,519
Selling, general and administrative expenses, excluding depreciation and amortization (1)	1,294,298		1,233,895		2,421,659	3,021,046	[1]
Selling, general and administrative expenses, excluding depreciation and amortization (1)	1,294,298		1,233,895		2,421,659	3,021,046	[1]
Grant and other revenue	0		51,007		0	51,007
Depreciation and amortization (2)	27,135		21,771		54,690	44,649	[2]
Depreciation and amortization (2)	27,135		21,771		54,690	44,649	[2]
Total revenue	0		57,526		0	57,526
Loss from operations	(2,427,698)		(2,922,601)		(4,850,067)	(5,901,884)	[3]
Loss from operations (3)	(2,427,698)		(2,922,601)		(4,850,067)	(5,901,884)	[3]
Cost of revenue, excluding depreciation and amortization			473			473
Other income, net (4)	1,034,514		(76,858)		1,980,553	(84,819)	[4]
Other expense, net (4)	1,034,514		(76,858)		1,980,553	(84,819)	[4]
Loss from continuing operations	(1,393,184)		(2,999,459)		(2,869,514)	(5,986,703)
Loss from continuing operations	(1,393,184)		(2,999,459)		(2,869,514)	(5,986,703)
United States	8,219,812				8,219,812			8,219,812	$ 4,371,606
United States	8,219,812				8,219,812			8,219,812	$ 4,371,606
Capital expenditures			48,657		15,068	48,657
Net loss	6,031,816	$ (1,476,330)	(2,999,459)	$ (2,987,245)	4,555,486	(5,986,703)
Non-US [Member]
United States	581,424		409,890		581,424	409,890		581,424
United States	581,424		409,890		581,424	409,890		581,424
Non-US [Member] | Sales Revenue [Member]
Revenue from Contract with Customer, Including Assessed Tax			6,519			6,519
UNITED STATES
United States	7,638,388		2,093,815		7,638,388	2,093,815		7,638,388
United States	7,638,388		2,093,815		7,638,388	2,093,815		7,638,388
Diagnostics Segment [Member]
Research and development expenses	1,057,046		1,636,691		2,227,599	2,626,578
Research and development expenses	1,057,046		1,636,691		2,227,599	2,626,578
Selling, general and administrative expenses, excluding depreciation and amortization (1)	0		0		0	0	[1]
Selling, general and administrative expenses, excluding depreciation and amortization (1)	0		0		0	0	[1]
Grant and other revenue			51,007			51,007
Depreciation and amortization (2)	9,527		6,041		18,802	12,081	[2]
Depreciation and amortization (2)	9,527		6,041		18,802	12,081	[2]
Total revenue			57,526			57,526
Loss from operations	(1,066,573)		(1,585,679)		(2,246,401)	(2,581,606)	[3]
Loss from operations (3)	(1,066,573)		(1,585,679)		(2,246,401)	(2,581,606)	[3]
Cost of revenue, excluding depreciation and amortization			473			473
Other income, net (4)	0		0		0	0	[4]
Other expense, net (4)	0		0		0	0	[4]
Loss from continuing operations	(1,066,573)				(2,246,401)
Loss from continuing operations	(1,066,573)				(2,246,401)
Capital expenditures			40,221		15,068	40,221
Net loss			(1,585,679)			(2,581,606)
Diagnostics Segment [Member] | Non-US [Member]
United States	568,856		384,294		568,856	384,294		568,856
United States	568,856		384,294		568,856	384,294		568,856
Diagnostics Segment [Member] | Non-US [Member] | Sales Revenue [Member]
Revenue from Contract with Customer, Including Assessed Tax			6,519			6,519
Diagnostics Segment [Member] | UNITED STATES
United States	0		50,000		0	50,000		0
United States	0		50,000		0	50,000		0
Therapeutics Segment [Member]
Research and development expenses	49,219		87,297		146,119	266,664
Research and development expenses	49,219		87,297		146,119	266,664
Selling, general and administrative expenses, excluding depreciation and amortization (1)	882		3,001		3,060	3,001	[1]
Selling, general and administrative expenses, excluding depreciation and amortization (1)	882		3,001		3,060	3,001	[1]
Grant and other revenue			0			0
Depreciation and amortization (2)	0		0		0	0	[2]
Depreciation and amortization (2)	0		0		0	0	[2]
Total revenue			0			0
Loss from operations	(50,101)		(90,298)		(149,179)	(269,665)	[3]
Loss from operations (3)	(50,101)		(90,298)		(149,179)	(269,665)	[3]
Cost of revenue, excluding depreciation and amortization			0			0
Other income, net (4)	0		0		0	0	[4]
Other expense, net (4)	0		0		0	0	[4]
Loss from continuing operations	(50,101)				(149,179)
Loss from continuing operations	(50,101)				(149,179)
Capital expenditures			0		0	0
Net loss			(90,298)			(269,665)
Therapeutics Segment [Member] | Non-US [Member]
United States	0		0		0	0		0
United States	0		0		0	0		0
Therapeutics Segment [Member] | Non-US [Member] | Sales Revenue [Member]
Revenue from Contract with Customer, Including Assessed Tax			0			0
Therapeutics Segment [Member] | UNITED STATES
United States	0		0		0	0		0
United States	0		0		0	0		0
Corporate Segment [Member]
Research and development expenses	0		0		0	0
Research and development expenses	0		0		0	0
Selling, general and administrative expenses, excluding depreciation and amortization (1)	1,293,416		1,230,894		2,418,599	3,018,045	[1]
Selling, general and administrative expenses, excluding depreciation and amortization (1)	1,293,416		1,230,894		2,418,599	3,018,045	[1]
Grant and other revenue			0			0
Depreciation and amortization (2)	17,608		15,730		35,888	32,568	[2]
Depreciation and amortization (2)	17,608		15,730		35,888	32,568	[2]
Total revenue			0			0
Loss from operations	(1,311,024)		(1,246,624)		(2,454,487)	(3,050,613)	[3]
Loss from operations (3)	(1,311,024)		(1,246,624)		(2,454,487)	(3,050,613)	[3]
Cost of revenue, excluding depreciation and amortization			0			0
Other income, net (4)	1,034,514		(76,858)		1,980,553	(84,819)	[4]
Other expense, net (4)	1,034,514		(76,858)		1,980,553	(84,819)	[4]
Loss from continuing operations	(276,510)				(473,934)
Loss from continuing operations	(276,510)				(473,934)
Capital expenditures			8,436		0	8,436
Net loss			(1,323,482)			(3,135,432)
Corporate Segment [Member] | Non-US [Member]
United States	12,568		25,596		12,568	25,596		12,568
United States	12,568		25,596		12,568	25,596		12,568
Corporate Segment [Member] | Non-US [Member] | Sales Revenue [Member]
Revenue from Contract with Customer, Including Assessed Tax			0			0
Corporate Segment [Member] | UNITED STATES
United States	7,638,388		2,043,815		7,638,388	2,043,815		7,638,388
United States	$ 7,638,388		$ 2,043,815		$ 7,638,388	$ 2,043,815		$ 7,638,388
[1]General and administrative expenses, excluding depreciation and amortization, represent costs that relate to the general administration of the Company and as such are not currently allocated to our individual reportable segments, other than those expenses directly incurred by Navidea Europe, Navidea UK and MT.[2]Depreciation and amortization are reflected in selling, general and administrative expenses ($27,135

Note 15 - Supplemental Disclo_2

Note 15 - Supplemental Disclosure for Statements of Cash Flows (Details Textual) - USD ($)		3 Months Ended				6 Months Ended
	Jun. 06, 2023	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Interest Paid, Excluding Capitalized Interest, Operating Activities						$ 98,201	$ 31,126
Stock Issued During Period, Shares, Employee Benefit Plan (in shares)						163,586	53,238
Stock Issued During Period, Value, Employee Benefit Plan			$ 52,348		$ 44,720	$ 52,348	$ 44,720
Issuance of Stock to Defined Contribution Plan for Employer Matching Contribution						52,348	$ 44,720
Stock Issued During Period, Value, New Issues		$ 1,089,000
Stock Issued During Period, Shares, Partial Repayment of Debt		1,073,600
Adjustments to Additional Paid in Capital, Deemed Dividends		$ 0				138,045
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability						$ 17,503
Conversion of Series J preferred Stock Into Common Stock [Member]
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)	11,969					11,969
Commitment Shares [Member] | Purchase Agreement [Member]
Stock Issued During Period, Shares, New Issues						200,000
Stock Issued During Period, Value, New Issues						$ 50,000
Common Stock [Member]
Stock Issued During Period, Shares, Employee Benefit Plan (in shares)			163,586		53,238
Stock Issued During Period, Value, Employee Benefit Plan			$ 164		$ 53
Stock Issued During Period, Shares, Issued for Employee Bonuses					16,632
Stock Issued During Period, Shares, New Issues		6,308,489
Stock Issued During Period, Value, New Issues		$ 6,308
Stock Issued During Period, Value, Partial Repayment of Debt		$ 12,200				$ 1,061,400
Stock Issued During Period, Shares, Partial Repayment of Debt		12,200,000				12,200,000
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)				0
Common Stock [Member] | Conversion from Series I Preferred Stock To Common Stock [Member]
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)		33,277,222				33,277,222
Common Stock [Member] | Conversion of Series J preferred Stock Into Common Stock [Member]
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)		11,508,672				11,508,672
Preferred Stock [Member]
Stock Issued During Period, Shares, Employee Benefit Plan (in shares)			0		0
Stock Issued During Period, Value, Employee Benefit Plan			$ 0		$ 0
Stock Issued During Period, Shares, Issued for Employee Bonuses					0
Stock Issued During Period, Shares, New Issues		11,000
Stock Issued During Period, Value, New Issues		$ 11
Stock Issued During Period, Value, Partial Repayment of Debt		$ 0
Stock Issued During Period, Shares, Partial Repayment of Debt		0
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)				(45,000)
Preferred Stock [Member] | Conversion from Series I Preferred Stock To Common Stock [Member]
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)		(5,335)				5,335
Preferred Stock [Member] | Conversion of Series J preferred Stock Into Common Stock [Member]
Stock Issued During Period, Shares, Conversion of Convertible Securities (in shares)		(11,969)				11,969
Employees [Member] | Common Stock [Member]
Stock Issued During Period, Shares, Issued for Employee Bonuses							16,632
Issuance of Stock to Defined Contribution Plan for Employer Matching Contribution							$ 16,965

Note 16 - Discontinued Operat_2

Note 16 - Discontinued Operations (Details Textual) - USD ($)					3 Months Ended	6 Months Ended
	Jun. 14, 2023	Apr. 09, 2018	Apr. 02, 2018	Mar. 03, 2017	Jun. 30, 2023	Jun. 30, 2023	Jun. 30, 2022
Gain (Loss) on Disposition of Assets						$ (1,377)	$ (62,388)
CRG [Member] | Letter of Credit [Member]
Proceeds from Issuance of Debt		$ 7,100,000
Sale of Assets to Cardinal Health 414 [Member]
Proceeds from Sale of Productive Assets	$ 7,500,000		$ 6,000,000	$ 80,600,000
Sale of Assets, Cash Received from Buyer, After Adjustments, Advances of Guaranteed Earnout Payments				$ 3,000,000
Sale of Assets, Maximum Amount Agreed to be Received, Benchmark					$ 7,100,000	7,100,000
Gain (Loss) on Disposition of Assets					7,400,000
Disposal Group, Including Discontinued Operation, Assets					0	0
Disposal Group, Including Discontinued Operation, Liabilities					$ 0	$ 0