ATTO Insider Transactions
461 retained open-market purchase and sale rows from SEC Forms 3, 4 and 5, newest first. This page shows rows 1–100; provenance stays internal.
ATTO insiders transaction timeline
PurchaseSale
| Insider profile | Role | Date | Transaction | Shares | Price |
|---|---|---|---|---|---|
| WALSH COLIN | Director | 2026-08-06 | Purchase | 500,000 | $17 |
| GOLDMAN SACHS & CO. LLC | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| GOLDMAN SACHS GROUP INC | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| GOLDMAN SACHS ASSET MANAGEMENT, L.P. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| Broad Street Principal Investments, L.L.C. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| West Street Life Sciences I, L.P. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| WSLS EMP OFFSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| WSLS OFFSHORE INVESTMENTS, SLP | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| WSLS EMP ONSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| WALSH COLIN | Director | 2026-08-06 | Purchase | 500,000 | $17 |
| GOLDMAN SACHS & CO. LLC | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| GOLDMAN SACHS GROUP INC | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| GOLDMAN SACHS ASSET MANAGEMENT, L.P. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| Broad Street Principal Investments, L.L.C. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| West Street Life Sciences I, L.P. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| WSLS EMP OFFSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| WSLS OFFSHORE INVESTMENTS, SLP | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| WSLS EMP ONSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-06 | Purchase | 500,000 | $17 |
| venBio Global Strategic Fund IV, L.P. | Ten Percent Owner | 2026-08-06 | Purchase | 382,352 | $17 |
| Sanofi | Ten Percent Owner | 2026-08-06 | Purchase | 300,000 | $17.00 |
| Redmile Group, LLC | Ten Percent Owner | 2026-08-06 | Purchase | 400,000 | $17.00 |
| Green Jeremy | Ten Percent Owner | 2026-08-06 | Purchase | 400,000 | $17.00 |
| Redmile Biopharma Investments III, L.P. | Ten Percent Owner | 2026-08-06 | Purchase | 400,000 | $17.00 |
| Redmile Group, LLC | Ten Percent Owner | 2026-08-06 | Purchase | 200,000 | $17.00 |
| Green Jeremy | Ten Percent Owner | 2026-08-06 | Purchase | 200,000 | $17.00 |
| Redmile Biopharma Investments III, L.P. | Ten Percent Owner | 2026-08-06 | Purchase | 200,000 | $17.00 |
| FHMLS XI, L.P. | Ten Percent Owner | 2026-08-06 | Purchase | 588,235 | $17 |
| Frazier Life Sciences XI, L.P. | Ten Percent Owner | 2026-08-06 | Purchase | 588,235 | $17 |
| FHMLS XI, L.L.C. | Ten Percent Owner | 2026-08-06 | Purchase | 588,235 | $17 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 480 | $21.55 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 200 | $22.10 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 3,402 | $22.02 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 1,556 | $22.06 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 200 | $22.05 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 1,332 | $22.03 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 447 | $21.87 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 76,418 | $21.04 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 6,763 | $21.61 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 100 | $21.99 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 1,163 | $22.19 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 700 | $22.07 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 988 | $22.03 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 200 | $22.05 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 443 | $21.78 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 300 | $20.84 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 1,040 | $22.05 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 1,180 | $21.84 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 400 | $22.02 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 6,970 | $22.03 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 672 | $22.02 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 753 | $21.97 |
| WALSH COLIN | Director | 2026-08-05 | Sale | 100 | $22.11 |
| WALSH COLIN | Director | 2026-08-05 | Purchase | 85,000 | $21 |
| GOLDMAN SACHS & CO. LLC | Former 10% Owner | 2026-08-05 | Sale | 480 | $21.55 |
| GOLDMAN SACHS GROUP INC | Former 10% Owner | 2026-08-05 | Sale | 480 | $21.55 |
| GOLDMAN SACHS ASSET MANAGEMENT, L.P. | Former 10% Owner | 2026-08-05 | Sale | 480 | $21.55 |
| Broad Street Principal Investments, L.L.C. | Former 10% Owner | 2026-08-05 | Sale | 480 | $21.55 |
| West Street Life Sciences I, L.P. | Former 10% Owner | 2026-08-05 | Sale | 480 | $21.55 |
| WSLS EMP OFFSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 480 | $21.55 |
| WSLS OFFSHORE INVESTMENTS, SLP | Former 10% Owner | 2026-08-05 | Sale | 480 | $21.55 |
| WSLS EMP ONSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 480 | $21.55 |
| GOLDMAN SACHS & CO. LLC | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.10 |
| GOLDMAN SACHS GROUP INC | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.10 |
| GOLDMAN SACHS ASSET MANAGEMENT, L.P. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.10 |
| Broad Street Principal Investments, L.L.C. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.10 |
| West Street Life Sciences I, L.P. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.10 |
| WSLS EMP OFFSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.10 |
| WSLS OFFSHORE INVESTMENTS, SLP | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.10 |
| WSLS EMP ONSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.10 |
| GOLDMAN SACHS & CO. LLC | Former 10% Owner | 2026-08-05 | Sale | 3,402 | $22.02 |
| GOLDMAN SACHS GROUP INC | Former 10% Owner | 2026-08-05 | Sale | 3,402 | $22.02 |
| GOLDMAN SACHS ASSET MANAGEMENT, L.P. | Former 10% Owner | 2026-08-05 | Sale | 3,402 | $22.02 |
| Broad Street Principal Investments, L.L.C. | Former 10% Owner | 2026-08-05 | Sale | 3,402 | $22.02 |
| West Street Life Sciences I, L.P. | Former 10% Owner | 2026-08-05 | Sale | 3,402 | $22.02 |
| WSLS EMP OFFSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 3,402 | $22.02 |
| WSLS OFFSHORE INVESTMENTS, SLP | Former 10% Owner | 2026-08-05 | Sale | 3,402 | $22.02 |
| WSLS EMP ONSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 3,402 | $22.02 |
| GOLDMAN SACHS & CO. LLC | Former 10% Owner | 2026-08-05 | Sale | 1,556 | $22.06 |
| GOLDMAN SACHS GROUP INC | Former 10% Owner | 2026-08-05 | Sale | 1,556 | $22.06 |
| GOLDMAN SACHS ASSET MANAGEMENT, L.P. | Former 10% Owner | 2026-08-05 | Sale | 1,556 | $22.06 |
| Broad Street Principal Investments, L.L.C. | Former 10% Owner | 2026-08-05 | Sale | 1,556 | $22.06 |
| West Street Life Sciences I, L.P. | Former 10% Owner | 2026-08-05 | Sale | 1,556 | $22.06 |
| WSLS EMP OFFSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 1,556 | $22.06 |
| WSLS OFFSHORE INVESTMENTS, SLP | Former 10% Owner | 2026-08-05 | Sale | 1,556 | $22.06 |
| WSLS EMP ONSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 1,556 | $22.06 |
| GOLDMAN SACHS & CO. LLC | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.05 |
| GOLDMAN SACHS GROUP INC | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.05 |
| GOLDMAN SACHS ASSET MANAGEMENT, L.P. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.05 |
| Broad Street Principal Investments, L.L.C. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.05 |
| West Street Life Sciences I, L.P. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.05 |
| WSLS EMP OFFSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.05 |
| WSLS OFFSHORE INVESTMENTS, SLP | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.05 |
| WSLS EMP ONSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 200 | $22.05 |
| GOLDMAN SACHS & CO. LLC | Former 10% Owner | 2026-08-05 | Sale | 1,332 | $22.03 |
| GOLDMAN SACHS GROUP INC | Former 10% Owner | 2026-08-05 | Sale | 1,332 | $22.03 |
| GOLDMAN SACHS ASSET MANAGEMENT, L.P. | Former 10% Owner | 2026-08-05 | Sale | 1,332 | $22.03 |
| Broad Street Principal Investments, L.L.C. | Former 10% Owner | 2026-08-05 | Sale | 1,332 | $22.03 |
| West Street Life Sciences I, L.P. | Former 10% Owner | 2026-08-05 | Sale | 1,332 | $22.03 |
| WSLS EMP OFFSHORE INVESTMENTS, L.P. | Former 10% Owner | 2026-08-05 | Sale | 1,332 | $22.03 |
| WSLS OFFSHORE INVESTMENTS, SLP | Former 10% Owner | 2026-08-05 | Sale | 1,332 | $22.03 |