Who owns SI-BONE, Inc. (SIBN)
Which tracked institutional funds hold SIBN, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See SIBN company fundamentals →
Ownership as of the 2026-Q1 13F filings (latest filed 2026-05-18). 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 SIBN is one-sided between 2025-Q4 and 2026-Q1: 19 added or opened and 82 trimmed or exited — on balance reducing.
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
SIBN’s largest tracked holder by dollar value, First Light Asset Management, LLC, sizes it at 6.1% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 6.1pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in SIBN 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 2025-Q4 and 2026-Q1, across 179 tracked filers holding SIBN, 96 increased or opened the position and 103 reduced or closed it; over the same quarter, open-market insider Form 4 buying and selling roughly offset.
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 SIBN between the 2025-Q4 and 2026-Q1 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 5
- VANGUARD CAPITAL MANAGEMENT LLC$22M
- VANGUARD PORTFOLIO MANAGEMENT LLC$5M
- VANGUARD FIDUCIARY TRUST CO$3M
- XTX Topco Ltd$1M
- Brevan Howard Capital Management LP$545K
Full exits 16
- VANGUARD GROUP INC$43M
- JANE STREET GROUP, LLC$5M
- Walleye Capital LLC$4M
- ExodusPoint Capital Management, LP$3M
- TWO SIGMA ADVISERS, LP$2M
- NORTHWESTERN MUTUAL WEALTH MANAGEMENT CO$2M
Largest adds
- GILDER GAGNON HOWE & CO LLC$5M
- MORGAN STANLEY$5M
- Granahan Investment Management, LLC$5M
- PARADIGM CAPITAL MANAGEMENT INC/NY$4M
- MILLENNIUM MANAGEMENT LLC$3M
- NEXT CENTURY GROWTH INVESTORS LLC$2M
Largest trims
- First Light Asset Management, LLC$32M
- BlackRock, Inc.$25M
- BROWN ADVISORY INC$22M
- AMERICAN CENTURY COMPANIES INC$14M
- Nuveen, LLC$12M
- SILVERCREST ASSET MANAGEMENT GROUP LLC$12M
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 |
|---|---|---|---|---|
| First Light Asset Management, LLC added | 5,353,190 | $68M | 10.0% | 2026-Q1 |
| BlackRock, Inc. trimmed | 3,428,541 | $43M | 6.4% | 2026-Q1 |
| AMERICAN CENTURY COMPANIES INC added | 2,509,065 | $32M | 4.7% | 2026-Q1 |
| BROWN ADVISORY INC trimmed | 2,122,332 | $27M | 4.0% | 2026-Q1 |
| CADIAN CAPITAL MANAGEMENT, LP added | 1,887,472 | $24M | 3.5% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 1,764,313 | $22M | 3.3% | 2026-Q1 |
| Granahan Investment Management, LLC added | 1,739,097 | $22M | 3.3% | 2026-Q1 |
| Impax Asset Management Group plc added | 1,425,010 | $18M | 2.7% | 2026-Q1 |
| Nuveen, LLC trimmed | 1,285,511 | $16M | 2.4% | 2026-Q1 |
| SILVERCREST ASSET MANAGEMENT GROUP LLC trimmed | 1,244,584 | $16M | 2.3% | 2026-Q1 |
| STATE STREET CORP added | 1,129,815 | $14M | 2.1% | 2026-Q1 |
| PARADIGM CAPITAL MANAGEMENT INC/NY added | 1,126,500 | $14M | 2.1% | 2026-Q1 |
| GILDER GAGNON HOWE & CO LLC added | 1,048,516 | $13M | 2.0% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 951,728 | $12M | 1.8% | 2026-Q1 |
| Champlain Investment Partners, LLC trimmed | 877,605 | $11M | 1.6% | 2026-Q1 |
| Point72 Asset Management, L.P. added | 840,346 | $11M | 1.6% | 2026-Q1 |
| MORGAN STANLEY added | 712,510 | $9M | 1.3% | 2026-Q1 |
| First Eagle Investment Management, LLC added | 638,941 | $8M | 1.2% | 2026-Q1 |
| WELLINGTON MANAGEMENT GROUP LLP trimmed | 630,518 | $8M | 1.2% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC trimmed | 622,442 | $8M | 1.2% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP added | 618,939 | $8M | 1.2% | 2026-Q1 |
| Pier Capital, LLC trimmed | 476,805 | $6M | 0.9% | 2026-Q1 |
| RENAISSANCE TECHNOLOGIES LLC added | 472,619 | $6M | 0.9% | 2026-Q1 |
| PEREGRINE CAPITAL MANAGEMENT LLC added | 428,061 | $5M | 0.8% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 419,473 | $5M | 0.8% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 413,494 | $5M | 0.8% | 2026-Q1 |
| NEXT CENTURY GROWTH INVESTORS LLC added | 383,958 | $5M | 0.7% | 2026-Q1 |
| Parkman Healthcare Partners LLC trimmed | 373,553 | $5M | 0.7% | 2026-Q1 |
| Qube Research & Technologies Ltd added | 371,526 | $5M | 0.7% | 2026-Q1 |
| ROYCE & ASSOCIATES LP added | 371,082 | $5M | 0.7% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC added | 369,303 | $5M | 0.7% | 2026-Q1 |
| NORTHERN TRUST CORP added | 358,337 | $5M | 0.7% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC trimmed | 315,471 | $4M | 0.6% | 2026-Q1 |
| TOCQUEVILLE ASSET MANAGEMENT L.P. | 304,000 | $4M | 0.6% | 2026-Q1 |
| SEI INVESTMENTS CO added | 284,769 | $4M | 0.5% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 274,691 | $3M | 0.5% | 2026-Q1 |
| HARBOR CAPITAL ADVISORS, INC. added | 246,795 | $3M | 0.5% | 2026-Q1 |
| ALGERT GLOBAL LLC trimmed | 230,412 | $3M | 0.4% | 2026-Q1 |
| Assenagon Asset Management S.A. trimmed | 224,004 | $3M | 0.4% | 2026-Q1 |
| ESSEX INVESTMENT MANAGEMENT CO LLC added | 212,488 | $3M | 0.4% | 2026-Q1 |
| D. E. Shaw & Co., Inc. trimmed | 189,028 | $2M | 0.4% | 2026-Q1 |
| CITADEL ADVISORS LLC trimmed | 188,226 | $2M | 0.4% | 2026-Q1 |
| VELA Investment Management, LLC added | 187,160 | $2M | 0.4% | 2026-Q1 |
| MARSHALL WACE, LLP trimmed | 166,993 | $2M | 0.3% | 2026-Q1 |
| HighMark Wealth Management LLC | 159,832 | $2M | 0.3% | 2026-Q1 |
| VICTORY CAPITAL MANAGEMENT INC trimmed | 151,960 | $2M | 0.3% | 2026-Q1 |
| Bullseye Asset Management LLC added | 142,732 | $2M | 0.3% | 2026-Q1 |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. added | 138,247 | $2M | 0.3% | 2026-Q1 |
| TUDOR INVESTMENT CORP ET AL trimmed | 130,116 | $2M | 0.2% | 2026-Q1 |
| Russell Investments Group, Ltd. trimmed | 122,804 | $2M | 0.2% | 2026-Q1 |
| JPMORGAN CHASE & CO trimmed | 125,099 | $2M | 0.2% | 2026-Q1 |
| LAZARD ASSET MANAGEMENT LLC trimmed | 102,499 | $1M | 0.2% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 100,642 | $1M | 0.2% | 2026-Q1 |
| Cinctive Capital Management LP added | 95,540 | $1M | 0.2% | 2026-Q1 |
| Engineers Gate Manager LP added | 94,924 | $1M | 0.2% | 2026-Q1 |
| Trexquant Investment LP trimmed | 89,259 | $1M | 0.2% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC added | 87,274 | $1M | 0.2% | 2026-Q1 |
| Squarepoint Ops LLC trimmed | 84,181 | $1M | 0.2% | 2026-Q1 |
| XTX Topco Ltd added | 83,153 | $1M | 0.2% | 2026-Q1 |
| Man Group plc added | 82,811 | $1M | 0.2% | 2026-Q1 |
| NANO CAP NEW MILLENNIUM GROWTH FUND L P added | 82,500 | $1M | 0.2% | 2026-Q1 |
| Swiss National Bank | 80,900 | $1M | 0.2% | 2026-Q1 |
| Caption Management, LLC added | 75,000 | $947K | 0.1% | 2026-Q1 |
| Universal- Beteiligungs- und Servicegesellschaft mbH trimmed | 74,229 | $938K | 0.1% | 2026-Q1 |
| CITIGROUP INC trimmed | 71,611 | $904K | 0.1% | 2026-Q1 |
| EverSource Wealth Advisors, LLC added | 2,414 | $897K | 0.1% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC added | 70,027 | $884K | 0.1% | 2026-Q1 |
| Legato Capital Management LLC trimmed | 66,597 | $841K | 0.1% | 2026-Q1 |
| ACADIAN ASSET MANAGEMENT LLC added | 63,199 | $795K | 0.1% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP trimmed | 58,147 | $734K | 0.1% | 2026-Q1 |
| AQR CAPITAL MANAGEMENT LLC added | 57,156 | $722K | 0.1% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. | 35,750 | $705K | 0.1% | 2026-Q1 |
| Invesco Ltd. trimmed | 55,528 | $701K | 0.1% | 2026-Q1 |
| Susquehanna Portfolio Strategies, LLC trimmed | 54,042 | $683K | 0.1% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC trimmed | 50,356 | $636K | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC trimmed | 2,185,864 | $43M | 6.4% | 2025-Q4 stale |
| ORBIMED ADVISORS LLC | 2,578,979 | $38M | 5.6% | 2025-Q3 stale |
| Holocene Advisors, LP | 585,311 | $11M | 1.6% | 2025-Q2 stale |
| Point72 (DIFC) Ltd added | 584,620 | $9M | 1.3% | 2025-Q3 stale |
| JANE STREET GROUP, LLC trimmed | 243,554 | $5M | 0.7% | 2025-Q4 stale |
| Walleye Capital LLC added | 194,120 | $4M | 0.6% | 2025-Q4 stale |
| Kent Lake PR LLC added | 250,000 | $4M | 0.5% | 2025-Q3 stale |
| Divisadero Street Capital Management, LP trimmed | 247,463 | $4M | 0.5% | 2025-Q3 stale |
| Cubist Systematic Strategies, LLC added | 246,911 | $4M | 0.5% | 2025-Q3 stale |
| ExodusPoint Capital Management, LP added | 170,431 | $3M | 0.5% | 2025-Q4 stale |
| TWO SIGMA ADVISERS, LP added | 113,600 | $2M | 0.3% | 2025-Q4 stale |
| NORTHWESTERN MUTUAL WEALTH MANAGEMENT CO added | 155,792 | $2M | 0.3% | 2025-Q4 stale |
| BALYASNY ASSET MANAGEMENT L.P. added | 104,838 | $2M | 0.3% | 2025-Q2 stale |
| Bellevue Group AG trimmed | 90,331 | $2M | 0.3% | 2025-Q4 stale |
| HUSSMAN STRATEGIC ADVISORS, INC. new | 84,000 | $2M | 0.2% | 2025-Q4 stale |
| MACQUARIE GROUP LTD added | 106,966 | $2M | 0.2% | 2025-Q3 stale |
| ADAGE CAPITAL PARTNERS GP, L.L.C. added | 75,000 | $1M | 0.2% | 2025-Q4 stale |
| PDT Partners, LLC | 69,116 | $1M | 0.2% | 2025-Q4 stale |
| Inspire Investing, LLC new | 63,168 | $1M | 0.2% | 2025-Q4 stale |
| Lisanti Capital Growth, LLC trimmed | 56,964 | $1M | 0.2% | 2025-Q4 stale |
| Schonfeld Strategic Advisors LLC added | 52,506 | $1M | 0.2% | 2025-Q4 stale |
| Connor, Clark & Lunn Investment Management Ltd. trimmed | 50,563 | $997K | 0.1% | 2025-Q4 stale |
| AMERIPRISE FINANCIAL INC added | 51,924 | $977K | 0.1% | 2025-Q2 stale |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC trimmed | 42,552 | $839K | 0.1% | 2025-Q4 stale |
| GSA CAPITAL PARTNERS LLP trimmed | 34,815 | $687K | 0.1% | 2025-Q4 stale |
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.