Xilio Therapeutics's top three insider shareholders as of September 09, 2026 are Impact Medicine Fund Lp Sv7 (TenPercentOwner, 3.23Mn shares), Capital Life Sciences Investors, Llc Bain (TenPercentOwner, 2.81Mn shares), James E Flynn (TenPercentOwner, 2.29Mn shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Impact Medicine Fund Lp Sv7 | TenPercentOwner | 1,613,632 | 1,613,632 | 3,227,264 | 29.4% | 03 Nov, 2021 |
| 2 | Capital Life Sciences Investors, Llc Bain | TenPercentOwner | 0 | 2,805,413 | 2,805,413 | 25.6% | 10 Dec, 2021 |
| 3 | James E Flynn | TenPercentOwner, Other | 0 | 2,287,944 | 2,287,944 | 20.9% | 28 Oct, 2021 |
| 4 | Springs Capital Management Lp Rock | TenPercentOwner | 0 | 1,256,472 | 1,256,472 | 11.5% | 26 Oct, 2021 |
| 5 | Sciences, Inc. Gilead | TenPercentOwner | 650,389 | 0 | 650,389 | 5.9% | 19 Dec, 2024 |
| 6 | Venture Fund Xi, L.P. Atlas | TenPercentOwner | 144,255 | 52,468 | 196,722 | 1.8% | 09 Feb, 2024 |
| 7 | Llc Fmr | Other | 0 | 136,262 | 136,262 | 1.2% | 28 Oct, 2021 |
| 8 | Pharmaceutical Co Ltd Takeda | TenPercentOwner | 0 | 105,366 | 105,366 | 1.0% | 26 Oct, 2021 |
| 9 | Venture Fund Iv, L.P. Rivervest | TenPercentOwner | 0 | 102,960 | 102,960 | 0.9% | 26 Oct, 2021 |
| 10 | City Capital Llc Bay | TenPercentOwner | 0 | 80,678 | 80,678 | 0.7% | 26 Oct, 2021 |
| 11 | Kgaa Merck | TenPercentOwner | 0 | 48,630 | 48,630 | 0.4% | 26 Oct, 2021 |
| 12 | Rene Russo | President And Ceo | 23,244 | 0 | 23,244 | 0.2% | 05 Jan, 2026 |
| 13 | Ltd Fil | Other | 0 | 15,622 | 15,622 | 0.1% | 28 Oct, 2021 |
| 14 | Venture Investments, Llc Alexandria | TenPercentOwner | 11,887 | 0 | 11,887 | 0.1% | 26 Oct, 2021 |
| 15 | James Samuel Shannon | Director | 10,000 | 0 | 10,000 | 0.1% | 30 Mar, 2026 |
| 16 | Christopher James Frankenfield | Chief Financial Officer | 2,656 | 0 | 2,656 | 0.0% | 05 Jan, 2026 |
| 17 | Katarina Luptakova | Chief Medical Officer | 2,375 | 0 | 2,375 | 0.0% | 05 Jan, 2026 |
| 18 | Kevin M. Brennan | Svp, Finance And Accounting | 683 | 0 | 683 | 0.0% | 05 Jan, 2026 |
Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.
| Date | Insider | Position | Transaction | Shares | Price | Value | Shares Held After | Ownership |
|---|---|---|---|---|---|---|---|---|
| 11 Jun, 2026 | Akintunde Olatokumbo Bello | Director | Acquired A | 5,000 | $0.00 | $0 | 5,000 | Direct |
| 11 Jun, 2026 | Sara Bonstein | Director | Acquired A | 5,000 | $0.00 | $0 | 5,000 | Direct |
| 11 Jun, 2026 | Yuan Xu | Director | Acquired A | 5,000 | $0.00 | $0 | 5,000 | Direct |
| 11 Jun, 2026 | Robert W. Ross | Director | Acquired A | 5,000 | $0.00 | $0 | 5,000 | Direct |
| 11 Jun, 2026 | Daniel J. Curran | Director | Acquired A | 5,000 | $0.00 | $0 | 5,000 | Direct |
| 11 Jun, 2026 | Aoife Brennan | Director | Acquired A | 5,000 | $0.00 | $0 | 5,000 | Direct |
| 11 Jun, 2026 | James Samuel Shannon | Director | Acquired A | 5,000 | $0.00 | $0 | 5,000 | Direct |
| 15 Apr, 2026 | Cheryl R Blanchard | Director | Acquired A | 10,000 | $0.00 | $0 | 10,000 | Direct |
| 26 Mar, 2026 | James Samuel Shannon | Director | Acquired P | 5,000 | $8.79 | $43.95K | 10,000 | Direct |
| 13 Feb, 2026 | Sciences, Inc. Gilead | TenPercentOwner | Acquired P | 3,739,000 | $7.49 | $28.00Mn | 2,884,590 | Direct |
| 01 Jan, 2026 | Christopher James Frankenfield | Chief Financial Officer | Acquired M | 19,375 | — | — | 2,271 | Direct |
| 01 Jan, 2026 | Rene Russo | President And Ceo | Acquired M | 44,250 | — | — | 23,244 | Direct |
| 01 Jan, 2026 | Katarina Luptakova | Chief Medical Officer | Acquired M | 16,625 | — | — | 2,375 | Direct |
| 01 Jan, 2026 | Kevin M. Brennan | Svp, Finance And Accounting | Acquired M | 5,000 | — | — | 586 | Direct |
| 31 Dec, 2025 | Katarina Luptakova | Chief Medical Officer | Acquired A | 451,885 | $0.00 | $0 | 32,278 | Direct |
| 02 Jan, 2026 | Kevin M. Brennan | Svp, Finance And Accounting | Disposed S | 1,826 | $9.00 | $16.44K | 455 | Direct |
| 31 Dec, 2025 | Rene Russo | President And Ceo | Acquired A | 1,500,258 | $0.00 | $0 | 107,161 | Direct |
| 02 Jan, 2026 | Christopher James Frankenfield | Chief Financial Officer | Disposed S | 7,030 | $9.00 | $63.30K | 1,769 | Direct |
| 01 Jan, 2026 | Katarina Luptakova | Chief Medical Officer | Disposed M | 16,625 | $0.00 | $0 | 2,375 | Direct |
| 31 Dec, 2025 | Christopher James Frankenfield | Chief Financial Officer | Acquired A | 668,789 | $0.00 | $0 | 47,771 | Direct |