ATAI's three largest insider shareholders as of May 30, 2026 are Investment Group Ltd. Apeiron (TenPercentOwner, 53.41Mn shares), Cosmo Feilding-Mellen (Director, 7.70Mn shares), Cosmo Feilding-Mellen (Director, 7.66Mn shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Investment Group Ltd. Apeiron | - | 0 | 53,412,414 | 02 Oct, 2025 |
| Florian Brand | - | 328,697 | 0 | 20 May, 2024 |
| Srinivas Rao | - | 212,942 | 0 | 24 Mar, 2025 |
| Sahil Kirpekar | Chief Business Officer | 115,636 | 0 | 24 Mar, 2025 |
| Anne Nagengast Johnson | Chief Financial Officer | 140,045 | 0 | 24 Mar, 2025 |
| Glenn Frank Short | Chief Scientific Officer | 42,333 | 0 | 24 Mar, 2025 |
| Kevin James Craig | Chief Medical Officer | 8,437 | 0 | 24 Mar, 2025 |
| Cosmo Feilding-Mellen | - | 7,702,990 | 0 | 06 Nov, 2025 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 25 Nov, 2025 | Cosmo Feilding-Mellen | Stock Option | D | 40,400 | $0.00 | 0 | D | D |
| 25 Nov, 2025 | Cosmo Feilding-Mellen | Stock Option | D | 40,400 | $0.00 | 0 | D | D |
| 25 Nov, 2025 | Cosmo Feilding-Mellen | Stock Option | A | 10,000 | $0.00 | 10,000 | D | A |
| 25 Nov, 2025 | Cosmo Feilding-Mellen | Stock Option | A | 10,000 | $0.00 | 10,000 | D | A |
| 04 Nov, 2025 | Scott Braunstein | Stock Option | A | 56,818 | $0.00 | 56,818 | D | A |
| 05 Nov, 2025 | Cosmo Feilding-Mellen | Common Shares | A | 7,702,990 | - | 7,702,990 | D | A |
| 05 Nov, 2025 | Cosmo Feilding-Mellen | Common Shares | A | 7,702,990 | - | 7,702,990 | D | A |
| 05 Nov, 2025 | Cosmo Feilding-Mellen | Stock Option | A | 103,000 | $0.00 | 103,000 | D | A |
| 05 Nov, 2025 | Cosmo Feilding-Mellen | Stock Option | A | 103,000 | $0.00 | 103,000 | D | A |
| 05 Nov, 2025 | Cosmo Feilding-Mellen | Stock Option | A | 40,400 | $0.00 | 40,400 | D | A |
| 05 Nov, 2025 | Cosmo Feilding-Mellen | Stock Option | A | 40,400 | $0.00 | 40,400 | D | A |
| 01 Oct, 2025 | Christopher Ryan Cave Barrett | Stock Option | A | 175,000 | $0.00 | 175,000 | D | A |
| 01 Oct, 2025 | Christopher Ryan Cave Barrett | Stock Option | A | 175,000 | $0.00 | 175,000 | D | A |
| 30 Sep, 2025 | Investment Group Ltd. Apeiron | Common Shares | A | 2,367,200 | - | 53,412,414 | I | C |
| 30 Sep, 2025 | Investment Group Ltd. Apeiron | Convertible Notes | D | 147,950 | - | 0 | I | C |
| 14 Aug, 2025 | Investment Group Ltd. Apeiron | Common Shares | A | 8,675,799 | $2.19 | 51,045,214 | I | P |
| 13 Aug, 2025 | Srinivas Rao | Stock Option | A | 650,794 | $0.00 | 650,794 | D | A |
| 13 Aug, 2025 | Srinivas Rao | Stock Option | A | 650,794 | $0.00 | 650,794 | D | A |
| 13 Aug, 2025 | Srinivas Rao | Stock Option | A | 217,777 | $0.00 | 217,777 | D | A |
| 13 Aug, 2025 | Srinivas Rao | Stock Option | A | 217,777 | $0.00 | 217,777 | D | A |