Who owns BLFS
Which tracked institutional funds hold BLFS, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See BLFS 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 BLFS is one-sided between 2025-Q4 and 2026-Q1: 19 added or opened and 71 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
BLFS’s largest tracked holder by dollar value, T. Rowe Price Investment Management, Inc., sizes it at 0.1% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.1pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in BLFS 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 187 tracked filers holding BLFS, 105 increased or opened the position and 88 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 BLFS 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 9
- VANGUARD CAPITAL MANAGEMENT LLC$37M
- VANGUARD PORTFOLIO MANAGEMENT LLC$17M
- CRAMER ROSENTHAL MCGLYNN LLC$12M
- VANGUARD FIDUCIARY TRUST CO$5M
- Man Group plc$1M
- Vestmark Advisory Solutions, Inc.$1M
Full exits 15
- VANGUARD GROUP INC$67M
- VOYA INVESTMENT MANAGEMENT LLC$12M
- Capricorn Fund Managers Ltd$9M
- DEERFIELD MANAGEMENT COMPANY, L.P.$3M
- TUDOR INVESTMENT CORP ET AL$3M
- SummitTX Capital, L.P.$2M
Largest adds
- T. Rowe Price Investment Management, Inc.$117M
- BANK OF AMERICA CORP /DE/$5M
- CITADEL ADVISORS LLC$2M
- Granahan Investment Management, LLC$2M
- BNP PARIBAS FINANCIAL MARKETS$1M
- Russell Investments Group, Ltd.$1M
Largest trims
- Invesco Ltd.$53M
- Casdin Capital, LLC$30M
- BlackRock, Inc.$27M
- FMR LLC$11M
- STATE STREET CORP$6M
- FRED ALGER MANAGEMENT, LLC$6M
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 |
|---|---|---|---|---|
| T. Rowe Price Investment Management, Inc. added | 6,506,346 | $124M | 11.6% | 2026-Q1 |
| BlackRock, Inc. added | 6,101,765 | $116M | 10.9% | 2026-Q1 |
| Casdin Capital, LLC | 5,957,165 | $114M | 10.6% | 2026-Q1 |
| Invesco Ltd. trimmed | 2,213,396 | $42M | 4.0% | 2026-Q1 |
| VANGUARD CAPITAL MANAGEMENT LLC new | 1,917,708 | $37M | 3.4% | 2026-Q1 |
| STATE STREET CORP added | 1,577,076 | $30M | 2.8% | 2026-Q1 |
| FMR LLC trimmed | 1,401,178 | $27M | 2.5% | 2026-Q1 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ added | 1,197,257 | $23M | 2.1% | 2026-Q1 |
| FRED ALGER MANAGEMENT, LLC trimmed | 1,079,935 | $21M | 1.9% | 2026-Q1 |
| DIMENSIONAL FUND ADVISORS LP added | 1,035,757 | $20M | 1.8% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC added | 971,927 | $19M | 1.7% | 2026-Q1 |
| BANK OF AMERICA CORP /DE/ added | 904,103 | $17M | 1.6% | 2026-Q1 |
| AMERIPRISE FINANCIAL INC trimmed | 901,138 | $17M | 1.6% | 2026-Q1 |
| ROYAL BANK OF CANADA added | 885,298 | $17M | 1.6% | 2026-Q1 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 865,038 | $17M | 1.5% | 2026-Q1 |
| PALISADE CAPITAL MANAGEMENT, LP trimmed | 758,659 | $14M | 1.4% | 2026-Q1 |
| Rockefeller Capital Management L.P. added | 741,352 | $14M | 1.3% | 2026-Q1 |
| GENEVA CAPITAL MANAGEMENT LLC trimmed | 739,803 | $14M | 1.3% | 2026-Q1 |
| Granahan Investment Management, LLC added | 722,057 | $14M | 1.3% | 2026-Q1 |
| Stephens Investment Management Group LLC added | 673,129 | $13M | 1.2% | 2026-Q1 |
| CRAMER ROSENTHAL MCGLYNN LLC added | 632,812 | $12M | 1.1% | 2026-Q1 |
| ROYCE & ASSOCIATES LP added | 584,011 | $11M | 1.0% | 2026-Q1 |
| MUTUAL OF AMERICA CAPITAL MANAGEMENT LLC trimmed | 572,729 | $11M | 1.0% | 2026-Q1 |
| GAGNON SECURITIES LLC added | 536,512 | $10M | 1.0% | 2026-Q1 |
| MORGAN STANLEY trimmed | 444,228 | $8M | 0.8% | 2026-Q1 |
| NORTHERN TRUST CORP added | 442,508 | $8M | 0.8% | 2026-Q1 |
| RAYMOND JAMES FINANCIAL INC added | 444,041 | $8M | 0.8% | 2026-Q1 |
| Curi Capital, LLC added | 426,015 | $8M | 0.8% | 2026-Q1 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 403,485 | $8M | 0.7% | 2026-Q1 |
| NEXT CENTURY GROWTH INVESTORS LLC added | 361,940 | $7M | 0.6% | 2026-Q1 |
| PEREGRINE CAPITAL MANAGEMENT LLC trimmed | 341,847 | $7M | 0.6% | 2026-Q1 |
| Summit Creek Advisors LLC added | 309,350 | $6M | 0.6% | 2026-Q1 |
| NEW YORK STATE COMMON RETIREMENT FUND | 298,618 | $6M | 0.5% | 2026-Q1 |
| VANGUARD FIDUCIARY TRUST CO new | 278,730 | $5M | 0.5% | 2026-Q1 |
| Gagnon Advisors, LLC | 274,217 | $5M | 0.5% | 2026-Q1 |
| Ranger Investment Management, L.P. trimmed | 269,365 | $5M | 0.5% | 2026-Q1 |
| Russell Investments Group, Ltd. added | 268,225 | $5M | 0.5% | 2026-Q1 |
| UBS Group AG added | 265,978 | $5M | 0.5% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 265,487 | $5M | 0.5% | 2026-Q1 |
| CITADEL ADVISORS LLC added | 244,172 | $5M | 0.4% | 2026-Q1 |
| ENVESTNET ASSET MANAGEMENT INC added | 242,439 | $5M | 0.4% | 2026-Q1 |
| Heights Point Management, LP added | 232,978 | $4M | 0.4% | 2026-Q1 |
| JPMORGAN CHASE & CO trimmed | 232,694 | $4M | 0.4% | 2026-Q1 |
| Bank of New York Mellon Corp trimmed | 211,310 | $4M | 0.4% | 2026-Q1 |
| RENAISSANCE TECHNOLOGIES LLC trimmed | 207,128 | $4M | 0.4% | 2026-Q1 |
| TD Asset Management Inc added | 193,348 | $4M | 0.3% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC added | 190,866 | $4M | 0.3% | 2026-Q1 |
| Uniplan Investment Counsel, Inc. trimmed | 182,837 | $3M | 0.3% | 2026-Q1 |
| Public Sector Pension Investment Board added | 139,513 | $3M | 0.2% | 2026-Q1 |
| ISTHMUS PARTNERS, LLC trimmed | 137,952 | $3M | 0.2% | 2026-Q1 |
| STATE OF WISCONSIN INVESTMENT BOARD added | 118,645 | $2M | 0.2% | 2026-Q1 |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. added | 111,592 | $2M | 0.2% | 2026-Q1 |
| SEI INVESTMENTS CO trimmed | 110,791 | $2M | 0.2% | 2026-Q1 |
| Nuveen, LLC trimmed | 109,182 | $2M | 0.2% | 2026-Q1 |
| D. E. Shaw & Co., Inc. trimmed | 101,870 | $2M | 0.2% | 2026-Q1 |
| Legal & General Group Plc trimmed | 97,209 | $2M | 0.2% | 2026-Q1 |
| WELLS FARGO & COMPANY/MN trimmed | 94,762 | $2M | 0.2% | 2026-Q1 |
| RHUMBLINE ADVISERS added | 94,579 | $2M | 0.2% | 2026-Q1 |
| Conestoga Capital Advisors, LLC added | 92,472 | $2M | 0.2% | 2026-Q1 |
| BARINGS LLC | 91,316 | $2M | 0.2% | 2026-Q1 |
| BNP PARIBAS FINANCIAL MARKETS added | 89,100 | $2M | 0.2% | 2026-Q1 |
| Swiss National Bank | 80,300 | $2M | 0.1% | 2026-Q1 |
| Rathbones Group PLC | 77,086 | $1M | 0.1% | 2026-Q1 |
| Man Group plc added | 72,626 | $1M | 0.1% | 2026-Q1 |
| ZACKS INVESTMENT MANAGEMENT added | 70,472 | $1M | 0.1% | 2026-Q1 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed | 67,797 | $1M | 0.1% | 2026-Q1 |
| Cerity Partners LLC added | 57,483 | $1M | 0.1% | 2026-Q1 |
| NEW YORK STATE TEACHERS RETIREMENT SYSTEM trimmed | 56,195 | $1M | 0.1% | 2026-Q1 |
| ALLIANCEBERNSTEIN L.P. trimmed | 43,882 | $1M | 0.1% | 2026-Q1 |
| Vestmark Advisory Solutions, Inc. added | 53,690 | $1M | 0.1% | 2026-Q1 |
| HSBC HOLDINGS PLC new | 45,576 | $874K | 0.1% | 2026-Q1 |
| KORNITZER CAPITAL MANAGEMENT INC /KS trimmed | 42,745 | $816K | 0.1% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 40,295 | $769K | 0.1% | 2026-Q1 |
| PRUDENTIAL FINANCIAL INC added | 39,852 | $760K | 0.1% | 2026-Q1 |
| CIBC Bancorp USA Inc. new | 39,778 | $759K | 0.1% | 2026-Q1 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 38,483 | $734K | 0.1% | 2026-Q1 |
| DEUTSCHE BANK AG\ added | 36,666 | $700K | 0.1% | 2026-Q1 |
| CANADA LIFE ASSURANCE Co | 34,692 | $663K | 0.1% | 2026-Q1 |
| SG Americas Securities, LLC added | 34,036 | $649K | 0.1% | 2026-Q1 |
| VANGUARD GROUP INC trimmed | 2,765,638 | $67M | 6.3% | 2025-Q4 stale |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC added | 946,623 | $22M | 2.0% | 2025-Q1 stale |
| VOYA INVESTMENT MANAGEMENT LLC trimmed | 496,937 | $12M | 1.1% | 2025-Q4 stale |
| Capricorn Fund Managers Ltd new | 378,550 | $9M | 0.9% | 2025-Q4 stale |
| Bard Financial Services, Inc. | 153,475 | $4M | 0.4% | 2025-Q3 stale |
| DEERFIELD MANAGEMENT COMPANY, L.P. added | 120,211 | $3M | 0.3% | 2025-Q4 stale |
| Point72 Asset Management, L.P. added | 113,030 | $3M | 0.3% | 2025-Q3 stale |
| TUDOR INVESTMENT CORP ET AL | 111,356 | $3M | 0.3% | 2025-Q4 stale |
| MACQUARIE GROUP LTD trimmed | 101,676 | $3M | 0.2% | 2025-Q3 stale |
| SummitTX Capital, L.P. new | 72,266 | $2M | 0.2% | 2025-Q4 stale |
| Squarepoint Ops LLC trimmed | 54,633 | $1M | 0.1% | 2025-Q3 stale |
| FIRST TRUST ADVISORS LP added | 50,354 | $1M | 0.1% | 2025-Q4 stale |
| JANE STREET GROUP, LLC trimmed | 43,966 | $1M | 0.1% | 2025-Q4 stale |
| Universal- Beteiligungs- und Servicegesellschaft mbH new | 40,653 | $929K | 0.1% | 2025-Q1 stale |
| ExodusPoint Capital Management, LP added | 36,055 | $920K | 0.1% | 2025-Q3 stale |
| CIBC Private Wealth Group LLC added | 37,697 | $912K | 0.1% | 2025-Q4 stale |
| Qube Research & Technologies Ltd trimmed | 33,410 | $808K | 0.1% | 2025-Q4 stale |
| SANDLER CAPITAL MANAGEMENT trimmed | 31,637 | $765K | 0.1% | 2025-Q4 stale |
| Gotham Asset Management, LLC trimmed | 29,812 | $761K | 0.1% | 2025-Q3 stale |
| MILLENNIUM MANAGEMENT LLC added | 27,698 | $707K | 0.1% | 2025-Q3 stale |
| Meros Investment Management, LP trimmed | 28,454 | $688K | 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.