Who owns Xilio Therapeutics (XLO)
Which tracked institutional funds hold XLO, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See XLO company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-09-22). 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
The tracked-fund tape on XLO is one-sided between 2026-Q1 and 2026-Q2: 7 added or opened and 1 trimmed or exited — on balance accumulating.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
XLO’s largest tracked holder by dollar value, Bain Capital Life Sciences Investors, LLC, sizes it at 0.4% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.4pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in XLO divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2026-Q1 and 2026-Q2, across 24 tracked filers holding XLO, 13 increased or opened the position and 12 reduced or closed it; over the same quarter, there were no open-market insider Form 4s.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in XLO between the 2026-Q1 and 2026-Q2 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 2
- ORBIMED ADVISORS LLC$6M
- ADAGE CAPITAL PARTNERS GP, L.L.C.$1M
Full exits 1
- Caligan Partners LP$943K
Largest adds
- Stonepine Capital Management, LLC$2M
- Bain Capital Life Sciences Investors, LLC$777K
- GILEAD SCIENCES, INC.$761K
- VANGUARD CAPITAL MANAGEMENT LLC$670K
- Frazier Life Sciences Management, L.P.$494K
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| Bain Capital Life Sciences Investors, LLC | 664,021 | $6M | 15.1% | 2026-Q2 |
| GILEAD SCIENCES, INC. | 650,389 | $6M | 14.8% | 2026-Q2 |
| ORBIMED ADVISORS LLC new | 592,300 | $6M | 13.5% | 2026-Q2 |
| Frazier Life Sciences Management, L.P. | 422,505 | $4M | 9.6% | 2026-Q2 |
| Stonepine Capital Management, LLC added | 225,994 | $2M | 5.1% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 178,517 | $2M | 4.1% | 2026-Q2 |
| Sio Capital Management, LLC | 152,464 | $1M | 3.5% | 2026-Q2 |
| ADAGE CAPITAL PARTNERS GP, L.L.C. new | 111,541 | $1M | 2.5% | 2026-Q2 |
| Merck & Co., Inc. | 105,982 | $1M | 2.4% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC added | 64,153 | $615K | 1.5% | 2026-Q2 |
| MORGAN STANLEY trimmed | 56,954 | $546K | 1.3% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 39,055 | $374K | 0.9% | 2026-Q2 |
| CITADEL ADVISORS LLC trimmed | 25,950 | $249K | 0.6% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO trimmed | 22,594 | $216K | 0.5% | 2026-Q2 |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC trimmed | 17,544 | $168K | 0.4% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP trimmed | 14,544 | $139K | 0.3% | 2026-Q2 |
| Velan Capital Investment Management LP | 14,285 | $137K | 0.3% | 2026-Q2 |
| STATE STREET CORP | 13,311 | $128K | 0.3% | 2026-Q2 |
| PRELUDE CAPITAL MANAGEMENT, LLC new | 11,600 | $111K | 0.3% | 2026-Q2 |
| Steward Partners Investment Advisory, LLC trimmed | 714 | $7K | 0.0% | 2026-Q2 |
| BARCLAYS PLC new | 115 | $1K | 0.0% | 2026-Q2 |
| Key Financial Inc | 59 | $565 | 0.0% | 2026-Q2 |
| JONES FINANCIAL COMPANIES LLLP new | 29 | $262 | 0.0% | 2026-Q2 |
| UBS Group AG trimmed | 14 | $134 | 0.0% | 2026-Q2 |
| Caligan Partners LP new | 112,128 | $943K | 2.2% | 2026-Q1 stale (1 quarter behind) |
| AJU IB Investment Co., Ltd. trimmed | 47,695 | $401K | 1.0% | 2026-Q1 stale (1 quarter behind) |
| FMR LLC trimmed | 36,558 | $307K | 0.7% | 2026-Q1 stale (1 quarter behind) |
| GSA CAPITAL PARTNERS LLP trimmed | 16,946 | $143K | 0.3% | 2026-Q1 stale (1 quarter behind) |
| Ghisallo Capital Management LLC trimmed | 13,800 | $116K | 0.3% | 2026-Q1 stale (1 quarter behind) |
| CWM, LLC new | 4,206 | $35K | 0.1% | 2026-Q1 stale (1 quarter behind) |
| JPMORGAN CHASE & CO added | 240 | $2K | 0.0% | 2026-Q1 stale (1 quarter behind) |
| Vanguard Global Advisers, LLC new | 210 | $2K | 0.0% | 2026-Q1 stale (1 quarter behind) |
| ROYAL BANK OF CANADA new | 91 | $1K | 0.0% | 2026-Q1 stale (1 quarter behind) |
| Point72 Asset Management, L.P. new | 4,000,000 | $3M | 6.1% | 2025-Q4 stale (2 quarters behind) |
| STEMPOINT CAPITAL LP new | 2,030,028 | $1M | 3.1% | 2025-Q4 stale (2 quarters behind) |
| VANGUARD GROUP INC | 1,255,692 | $804K | 1.9% | 2025-Q4 stale (2 quarters behind) |
| Empery Asset Management, LP new | 1,183,040 | $757K | 1.8% | 2025-Q4 stale (2 quarters behind) |
| NORTHERN TRUST CORP | 66,609 | $43K | 0.1% | 2025-Q4 stale (2 quarters behind) |
| JANE STREET GROUP, LLC new | 42,080 | $27K | 0.1% | 2025-Q4 stale (2 quarters behind) |
| HRT FINANCIAL LP added | 31,886 | $20K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| Mariner, LLC | 25,000 | $16K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| LPL Financial LLC trimmed | 21,000 | $13K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| RAYMOND JAMES FINANCIAL INC | 18,761 | $12K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| XTX Topco Ltd trimmed | 17,304 | $11K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| Dunhill Financial, LLC | 10,274 | $7K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| INVESTORS ASSET MANAGEMENT OF GEORGIA INC /GA/ /ADV | 10,000 | $6K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| Pinnacle Financial Group, LLC / IL | 10,000 | $6K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| BlackRock, Inc. | 2,037 | $1K | 0.0% | 2025-Q4 stale (2 quarters behind) |
| Private Wealth Management Group, LLC | 310 | $199 | 0.0% | 2025-Q4 stale (2 quarters behind) |
| BANK OF AMERICA CORP /DE/ added | 261 | $167 | 0.0% | 2025-Q4 stale (2 quarters behind) |
| TAKEDA PHARMACEUTICAL CO LTD | 1,475,121 | $1M | 3.0% | 2025-Q3 stale (3 quarters behind) |
| Squarepoint Ops LLC added | 328,794 | $277K | 0.7% | 2025-Q3 stale (3 quarters behind) |
| Trustees of Columbia University in the City of New York | 249,635 | $210K | 0.5% | 2025-Q3 stale (3 quarters behind) |
| BALYASNY ASSET MANAGEMENT L.P. | 198,859 | $168K | 0.4% | 2025-Q3 stale (3 quarters behind) |
| TWO SIGMA SECURITIES, LLC trimmed | 32,130 | $27K | 0.1% | 2025-Q3 stale (3 quarters behind) |
| TWO SIGMA ADVISERS, LP new | 29,689 | $25K | 0.1% | 2025-Q3 stale (3 quarters behind) |
| Aptus Capital Advisors, LLC | 25,000 | $21K | 0.1% | 2025-Q3 stale (3 quarters behind) |
| SevenBridge Financial Group, LLC | 25,000 | $19K | 0.0% | 2025-Q3 stale (3 quarters behind) |
| Federation des caisses Desjardins du Quebec | 3,300 | $3K | 0.0% | 2025-Q3 stale (3 quarters behind) |
| CITIGROUP INC new | 258 | $217 | 0.0% | 2025-Q3 stale (3 quarters behind) |
| Avantax Planning Partners, Inc. trimmed | 142,338 | $97K | 0.2% | 2025-Q2 stale (4 quarters behind) |
| Tower Research Capital LLC (TRC) added | 15,412 | $10K | 0.0% | 2025-Q2 stale (4 quarters behind) |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | 0 | — | 0.0% | 2025-Q2 stale (4 quarters behind) |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.