CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Current assets:
Cash and cash equivalents	$ 61,940	$ 17,505
Securities carried at fair value	34,003	44,825
Short-term restricted cash for other investments	0	10,000
Prepaid expenses and other current assets	6,738	7,795
Total current assets	102,681	80,125
Property and equipment, net	2,899	2,535
Operating lease right-of-use asset, net	2,803	1,334
Other Investments held at fair value	16,816	28,887
Other investments	53,947	42,079
Intangible assets, net	3,122	3,246
Goodwill	331	331
Digital assets	6,216	0
Other assets	389	850
Total assets	189,204	159,387
Current liabilities:
Accounts payable	4,039	2,616
Accrued liabilities	14,514	9,847
Current portion of lease liabilities	437	477
Short-term convertible promissory notes and derivative liability - related party	2,466	1,150
Short-term convertible promissory notes and derivative liability	3,694	1,840
Current portion of long-term debt	0	6,374
Other current liabilities	397	2,647
Total current liabilities	25,547	24,951
Contingent consideration liability - related party	110	110
Contingent consideration liability	212	212
Non-current portion of lease liability	2,619	732
Pre-funded warrant liabilities	13,758	0
Long-term debt, net	0	14,133
Other liabilities	3,033	2,695
Total liabilities	45,279	42,833
Commitments and Contingencies (Note 19)
Equity, Attributable to Parent [Abstract]
Common stock, 0.10 par value ($0.12 and $0.10 par value at June 30, 2025 and December 31, 2024, respectively); 750,000,000 shares authorized at June 30, 2025 and December 31, 2024, respectively; 212,244,597 and 167,959,752 shares issued and outstanding at June 30, 2025 and December 31, 2024, respectively	23,547	18,785
Additional paid-in capital	895,486	816,185
Accumulated other comprehensive loss	(20,928)	(18,466)
Accumulated deficit	(754,367)	(700,207)
Total stockholders' equity attributable to ATAI Life Sciences N.V. stockholders	143,738	116,297
Noncontrolling interests	187	257
Total stockholders equity	143,925	116,554
Total liabilities and stockholders' equity	$ 189,204	$ 159,387