Prothena Corporation Public (PRTA) Annual Balance Sheet

Balance Sheet Summary

Prothena Corporation Public (PRTA) annual balance sheet covering fiscal 2020 through 2025, as reported to the SEC.

Prothena Corporation Public had total assets of $326.8M and total liabilities of $46.33M as of December 31, 2025. That leaves shareholders' equity of $280.47M.
Total assets were down 40.3% from $547.11M in fiscal 2024.
Total current assets of $315.19M were 7.7 times total current liabilities of $40.84M.
Cash and cash equivalents were $307.53M, down 34.8% from $471.39M. That is 94.1% of total assets.
Prothena Corporation Public has an accumulated deficit of $1.35B.

Total assets have shrunk 0.37% a year on average since fiscal 2020, from $332.98M to $326.8M.

A balance sheet shows what a company owns and what it owes on a single date. The difference between the two belongs to shareholders.

Figures in USD thousands

						Dec'25	Dec'24	Dec'23	Dec'22	Dec'21	Dec'20
Assets
Current assets:
Cash and cash equivalents
307,531	471,388	618,830	710,406	579,094	295,380	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Cash and cash equivalents						307,531	471,388	618,830	710,406	579,094	295,380	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Accounts receivable
-	-	5,159	-	-	15	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Accounts receivable						-	-	5,159	-	-	15	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Receivable from related party
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Receivable from related party						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred tax assets
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred tax assets						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Prepaid expenses and other current assets
7,662	14,024	13,941	8,692	5,715	2,537	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Prepaid expenses and other current assets						7,662	14,024	13,941	8,692	5,715	2,537	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restricted cash, current
-	-	1,352	-	-	1,352	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restricted cash, current						-	-	1,352	-	-	1,352	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total current assets
315,193	485,412	639,282	719,098	584,809	299,284	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total current assets						315,193	485,412	639,282	719,098	584,809	299,284	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Non-current assets:
Property and equipment, net
2,144	3,081	3,836	1,731	2,012	2,551	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Property and equipment, net						2,144	3,081	3,836	1,731	2,012	2,551	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Operating lease right-of-use assets
8,125	10,708	12,162	6,277	12,123	17,811	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Operating lease right-of-use assets						8,125	10,708	12,162	6,277	12,123	17,811	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred tax assets
-	43,239	33,893	18,204	7,071	11,644	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred tax assets						-	43,239	33,893	18,204	7,071	11,644	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred tax assets
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred tax assets						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restricted cash, non-current
860	860	860	2,212	1,352	1,352	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restricted cash, non-current						860	860	860	2,212	1,352	1,352	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restricted cash
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restricted cash						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restricted cash
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restricted cash						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Other non-current assets
482	3,808	6,349	10,513	1,999	333	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Other non-current assets						482	3,808	6,349	10,513	1,999	333	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total non-current assets
11,611	61,696	57,100	38,937	24,557	33,691	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total non-current assets						11,611	61,696	57,100	38,937	24,557	33,691	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total assets
326,804	547,108	696,382	758,035	609,366	332,975	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total assets						326,804	547,108	696,382	758,035	609,366	332,975	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Liabilities and Shareholders’ Equity
Current liabilities:
Accounts payable
5,875	7,770	25,391	9,270	3,691	4,117	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Accounts payable						5,875	7,770	25,391	9,270	3,691	4,117	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Accrued research and development
4,329	13,428	14,724	10,794	6,351	9,044	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Accrued research and development						4,329	13,428	14,724	10,794	6,351	9,044	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Income taxes payable, current
-	-	-	-	-	36	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Income taxes payable, current						-	-	-	-	-	36	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred revenue, current
2,664	8,850	-	11,442	7,657	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred revenue, current						2,664	8,850	-	11,442	7,657	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Build-to-suit lease obligation, current
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Build-to-suit lease obligation, current						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restructuring liability
13,303	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Restructuring liability						13,303	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Lease liability, current
2,886	2,610	1,114	6,473	5,940	5,512	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Lease liability, current						2,886	2,610	1,114	6,473	5,940	5,512	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Other current liabilities
11,786	15,843	15,662	12,168	9,813	7,139	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Other current liabilities						11,786	15,843	15,662	12,168	9,813	7,139	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total current liabilities
40,843	48,501	56,891	50,147	33,452	25,848	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total current liabilities						40,843	48,501	56,891	50,147	33,452	25,848	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Non-current liabilities:
Deferred revenue, non-current
-	3,448	67,405	85,293	102,933	110,242	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred revenue, non-current						-	3,448	67,405	85,293	102,933	110,242	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Income taxes payable, non-current
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Income taxes payable, non-current						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred rent
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Deferred rent						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Lease liability, non-current
5,487	8,233	10,721	-	6,386	12,326	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Lease liability, non-current						5,487	8,233	10,721	-	6,386	12,326	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Build-to-suit lease obligation, non-current
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Build-to-suit lease obligation, non-current						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Other Liabilities, Noncurrent
-	-	-	553	553	553	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Other Liabilities, Noncurrent						-	-	-	553	553	553	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total non-current liabilities
5,487	11,681	78,126	85,846	109,872	123,121	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total non-current liabilities						5,487	11,681	78,126	85,846	109,872	123,121	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total liabilities
46,330	60,182	135,017	135,993	143,324	148,969	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total liabilities						46,330	60,182	135,017	135,993	143,324	148,969	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Commitments and contingencies (Note 6)
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Commitments and contingencies (Note 6)						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Shareholders’ equity:
Euro deferred shares, €22 nominal value: Authorized shares — 10,000 at June 30, 2026 and December 31, 2025 and Issued and outstanding shares — none at June 30, 2026 and December 31, 2025
-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Euro deferred shares, €22 nominal value: Authorized shares — 10,000 at June 30, 2026 and December 31, 2025 and Issued and outstanding shares — none at June 30, 2026 and December 31, 2025						-	-	-	-	-	-	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Ordinary shares, $0.01 par value: Authorized shares — 100,000,000 at June 30, 2026 and December 31, 2025 and Issued and outstanding shares — 51,744,327 and 53,832,982 at June 30, 2026 and December 31, 2025, respectively
538	538	537	521	466	399	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Ordinary shares, $0.01 par value: Authorized shares — 100,000,000 at June 30, 2026 and December 31, 2025 and Issued and outstanding shares — 51,744,327 and 53,832,982 at June 30, 2026 and December 31, 2025, respectively						538	538	537	521	466	399	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Additional paid-in capital
1,626,369	1,588,729	1,540,859	1,454,524	1,181,630	966,636	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Additional paid-in capital						1,626,369	1,588,729	1,540,859	1,454,524	1,181,630	966,636	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Accumulated deficit
-1,346,433	-1,102,341	-980,031	-833,003	-716,054	-783,029	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Accumulated deficit						-1,346,433	-1,102,341	-980,031	-833,003	-716,054	-783,029	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total shareholders’ equity
280,474	486,926	561,365	622,042	466,042	184,006	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total shareholders’ equity						280,474	486,926	561,365	622,042	466,042	184,006	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total liabilities and shareholders’ equity
326,804	547,108	696,382	758,035	609,366	332,975	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx
Total liabilities and shareholders’ equity						326,804	547,108	696,382	758,035	609,366	332,975	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx	xxxxx