Who owns Cabaletta Bio (CABA)
Which tracked institutional funds hold CABA, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See CABA company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-08-17). 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 CABA is one-sided between 2026-Q1 and 2026-Q2: 42 added or opened and 13 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
CABA’s largest tracked holder by dollar value, JENNISON ASSOCIATES LLC, sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.0pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in CABA 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 134 tracked filers holding CABA, 99 increased or opened the position and 46 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 CABA 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 12
- NORGES BANK$13M
- CITADEL ADVISORS LLC$11M
- FRANKLIN RESOURCES INC$8M
- VANGUARD PORTFOLIO MANAGEMENT LLC$4M
- SPHERA FUNDS MANAGEMENT LTD.$4M
- AMERIPRISE FINANCIAL INC$3M
Full exits 5
- T. Rowe Price Investment Management, Inc.$30M
- GSA CAPITAL PARTNERS LLP$2M
- JANE STREET GROUP, LLC$669K
- Point72 Asset Management, L.P.$663K
- 683 Capital Management, LLC$605K
Largest adds
- JENNISON ASSOCIATES LLC$38M
- Bain Capital Life Sciences Investors, LLC$28M
- BlackRock, Inc.$27M
- STATE STREET CORP$23M
- PRICE T ROWE ASSOCIATES INC /MD/$13M
- VANGUARD CAPITAL MANAGEMENT LLC$12M
Largest trims
- MILLENNIUM MANAGEMENT LLC$9M
- TWO SIGMA INVESTMENTS, LP$2M
- MARSHALL WACE, LLP$994K
- Qube Research & Technologies Ltd$768K
- RENAISSANCE TECHNOLOGIES LLC$704K
- Almitas Capital LLC$516K
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 |
|---|---|---|---|---|
| JENNISON ASSOCIATES LLC added | 20,033,730 | $62M | 12.9% | 2026-Q2 |
| Bain Capital Life Sciences Investors, LLC added | 17,241,445 | $54M | 11.1% | 2026-Q2 |
| BlackRock, Inc. added | 10,754,701 | $33M | 6.9% | 2026-Q2 |
| ADAGE CAPITAL PARTNERS GP, L.L.C. added | 9,174,758 | $29M | 5.9% | 2026-Q2 |
| STATE STREET CORP added | 7,839,305 | $24M | 5.0% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 7,227,018 | $22M | 4.6% | 2026-Q2 |
| Cormorant Asset Management, LP trimmed | 5,000,000 | $16M | 3.2% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ added | 4,418,674 | $14M | 2.8% | 2026-Q2 |
| Woodline Partners LP added | 4,200,142 | $13M | 2.7% | 2026-Q2 |
| NORGES BANK new | 4,112,401 | $13M | 2.6% | 2026-Q2 |
| Opaleye Management Inc. added | 3,863,800 | $12M | 2.5% | 2026-Q2 |
| CITADEL ADVISORS LLC added | 3,522,112 | $11M | 2.3% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 3,459,464 | $11M | 2.2% | 2026-Q2 |
| FRANKLIN RESOURCES INC new | 2,413,937 | $8M | 1.6% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC added | 2,211,825 | $7M | 1.4% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC trimmed | 2,068,491 | $6M | 1.3% | 2026-Q2 |
| MARSHALL WACE, LLP trimmed | 1,565,939 | $5M | 1.0% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC trimmed | 1,535,300 | $5M | 1.0% | 2026-Q2 |
| UBS Group AG added | 1,471,895 | $5M | 0.9% | 2026-Q2 |
| Qube Research & Technologies Ltd trimmed | 1,426,840 | $4M | 0.9% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC new | 1,418,108 | $4M | 0.9% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP trimmed | 1,410,931 | $4M | 0.9% | 2026-Q2 |
| MORGAN STANLEY trimmed | 1,345,526 | $4M | 0.9% | 2026-Q2 |
| SPHERA FUNDS MANAGEMENT LTD. new | 1,329,012 | $4M | 0.9% | 2026-Q2 |
| SUPERSTRING CAPITAL MANAGEMENT LP added | 1,278,652 | $3M | 0.7% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 1,088,595 | $3M | 0.7% | 2026-Q2 |
| NORTHERN TRUST CORP added | 1,007,102 | $3M | 0.6% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP added | 967,195 | $3M | 0.6% | 2026-Q2 |
| Stonepine Capital Management, LLC added | 917,100 | $3M | 0.6% | 2026-Q2 |
| SCHRODER INVESTMENT MANAGEMENT GROUP added | 856,637 | $3M | 0.6% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC new | 828,145 | $3M | 0.5% | 2026-Q2 |
| CANTOR FITZGERALD, L. P. added | 800,001 | $2M | 0.5% | 2026-Q2 |
| HEIGHTS CAPITAL MANAGEMENT, INC trimmed | 755,626 | $2M | 0.5% | 2026-Q2 |
| Blue Owl Capital Holdings LP trimmed | 714,710 | $2M | 0.5% | 2026-Q2 |
| Ikarian Capital, LLC trimmed | 700,000 | $2M | 0.4% | 2026-Q2 |
| Burkehill Global Management, LP | 700,000 | $2M | 0.4% | 2026-Q2 |
| Nuveen, LLC added | 646,345 | $2M | 0.4% | 2026-Q2 |
| KVP Capital Advisors, LP | 505,431 | $2M | 0.3% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ added | 493,314 | $2M | 0.3% | 2026-Q2 |
| Jump Financial, LLC added | 488,775 | $2M | 0.3% | 2026-Q2 |
| Raiffeisen Bank International AG trimmed | 430,000 | $1M | 0.3% | 2026-Q2 |
| TD Asset Management Inc added | 391,472 | $1M | 0.3% | 2026-Q2 |
| Susquehanna Portfolio Strategies, LLC added | 383,294 | $1M | 0.2% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 374,886 | $1M | 0.2% | 2026-Q2 |
| Sixth Street Partners Management Company, L.P. new | 374,886 | $1M | 0.2% | 2026-Q2 |
| Bank of New York Mellon Corp added | 304,819 | $948K | 0.2% | 2026-Q2 |
| WELLINGTON MANAGEMENT GROUP LLP added | 286,212 | $890K | 0.2% | 2026-Q2 |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC | 267,372 | $832K | 0.2% | 2026-Q2 |
| Invesco Ltd. added | 241,565 | $751K | 0.2% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN added | 196,872 | $612K | 0.1% | 2026-Q2 |
| CITIGROUP INC added | 184,232 | $573K | 0.1% | 2026-Q2 |
| BOOTHBAY FUND MANAGEMENT, LLC trimmed | 182,455 | $567K | 0.1% | 2026-Q2 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE added | 182,055 | $566K | 0.1% | 2026-Q2 |
| PANAGORA ASSET MANAGEMENT INC trimmed | 161,916 | $504K | 0.1% | 2026-Q2 |
| SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC new | 152,964 | $476K | 0.1% | 2026-Q2 |
| Rafferty Asset Management, LLC new | 146,107 | $454K | 0.1% | 2026-Q2 |
| Diametric Capital, LP trimmed | 135,598 | $422K | 0.1% | 2026-Q2 |
| RHUMBLINE ADVISERS added | 131,640 | $409K | 0.1% | 2026-Q2 |
| Almitas Capital LLC trimmed | 125,900 | $392K | 0.1% | 2026-Q2 |
| DEUTSCHE BANK AG\ added | 110,962 | $345K | 0.1% | 2026-Q2 |
| Virtus Investment Advisers, LLC new | 108,703 | $338K | 0.1% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. added | 108,410 | $292K | 0.1% | 2026-Q2 |
| D. E. Shaw & Co., Inc. trimmed | 90,652 | $282K | 0.1% | 2026-Q2 |
| LETKO, BROSSEAU & ASSOCIATES INC | 90,475 | $281K | 0.1% | 2026-Q2 |
| Graham Capital Management, L.P. trimmed | 81,279 | $253K | 0.1% | 2026-Q2 |
| LPL Financial LLC added | 79,075 | $246K | 0.1% | 2026-Q2 |
| PROFUND ADVISORS LLC new | 73,409 | $228K | 0.0% | 2026-Q2 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. added | 68,592 | $213K | 0.0% | 2026-Q2 |
| MetLife Investment Management, LLC added | 66,749 | $208K | 0.0% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP trimmed | 63,228 | $197K | 0.0% | 2026-Q2 |
| RAYMOND JAMES FINANCIAL INC added | 60,289 | $187K | 0.0% | 2026-Q2 |
| JPMORGAN CHASE & CO added | 59,368 | $185K | 0.0% | 2026-Q2 |
| Vanguard Global Advisers, LLC added | 57,372 | $178K | 0.0% | 2026-Q2 |
| MATAURO, LLC | 55,108 | $171K | 0.0% | 2026-Q2 |
| Universal- Beteiligungs- und Servicegesellschaft mbH new | 54,086 | $168K | 0.0% | 2026-Q2 |
| EntryPoint Capital, LLC new | 50,927 | $158K | 0.0% | 2026-Q2 |
| ADAR1 Capital Management, LLC new | 50,000 | $156K | 0.0% | 2026-Q2 |
| T. Rowe Price Investment Management, Inc. added | 11,080,005 | $30M | 6.2% | 2026-Q1 stale |
| VANGUARD GROUP INC added | 4,419,458 | $10M | 2.0% | 2025-Q4 stale |
| Alyeska Investment Group, L.P. trimmed | 1,300,000 | $3M | 0.6% | 2025-Q3 stale |
| Anson Funds Management LP new | 1,822,830 | $3M | 0.6% | 2025-Q2 stale |
| TWO SIGMA ADVISERS, LP added | 737,900 | $2M | 0.3% | 2025-Q4 stale |
| GSA CAPITAL PARTNERS LLP added | 561,726 | $2M | 0.3% | 2026-Q1 stale |
| Ensign Peak Advisors, Inc added | 550,000 | $1M | 0.2% | 2025-Q4 stale |
| Integral Health Asset Management, LLC added | 850,000 | $1M | 0.2% | 2025-Q1 stale |
| JANE STREET GROUP, LLC trimmed | 248,594 | $669K | 0.1% | 2026-Q1 stale |
| Point72 Asset Management, L.P. added | 246,615 | $663K | 0.1% | 2026-Q1 stale |
| 683 Capital Management, LLC trimmed | 225,000 | $605K | 0.1% | 2026-Q1 stale |
| Hudson Bay Capital Management LP added | 161,726 | $435K | 0.1% | 2026-Q1 stale |
| ACADIAN ASSET MANAGEMENT LLC added | 186,521 | $433K | 0.1% | 2025-Q3 stale |
| AXA S.A. added | 270,516 | $411K | 0.1% | 2025-Q2 stale |
| Brevan Howard Capital Management LP new | 149,721 | $403K | 0.1% | 2026-Q1 stale |
| Squarepoint Ops LLC trimmed | 144,681 | $389K | 0.1% | 2026-Q1 stale |
| ExodusPoint Capital Management, LP new | 105,985 | $285K | 0.1% | 2026-Q1 stale |
| FEDERATED HERMES, INC. trimmed | 112,028 | $262K | 0.1% | 2025-Q3 stale |
| NOMURA HOLDINGS INC new | 95,512 | $257K | 0.1% | 2026-Q1 stale |
| Atle Fund Management AB trimmed | 182,354 | $253K | 0.1% | 2025-Q1 stale |
| Quadrature Capital Ltd added | 87,060 | $234K | 0.0% | 2026-Q1 stale |
| OMERS ADMINISTRATION Corp trimmed | 54,100 | $146K | 0.0% | 2026-Q1 stale |
| Thrivent Financial for Lutherans | 95,327 | $145K | 0.0% | 2025-Q2 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.