Mass General Brigham, Inc — 13F Holdings & Portfolio
CIK 1678378 · latest 13F-HR filed 2026-05-05
Mass General Brigham, Inc manages $468.9M in 13F-reported U.S. long-equity assets across 6 reported positions as of its 2026-03-31 13F-HR filing. Its largest disclosed positions are ACWI (62.42%), KRMN (26.67%), RVMD (7.14%). Quarter over quarter (versus its 2025-12-31 filing) the fund opened 0 new positions, exited 1, added to 4, and trimmed 2.
AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.
$468.9M
Long-equity book
6
Distinct positions
2026-03-31
Filed 2026-05-05
+0 / −1 / ↑4 / ↓2
vs 2025-12-31
| Name | Title / Status | Ownership | Type |
|---|
Top Adds (vs prior quarter)
- KARMAN HLDGS INC$10.7M +9.4%
- REVOLUTION MEDICINES INC$6.1M +22.1%
- TANGO THERAPEUTICS INC$4.3M +136.1%
- MEDLINE INC$2.0M +183.5%
Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).
| # | Issuer | Symbol | CUSIP | Value | Weight | Shares | Type |
|---|---|---|---|---|---|---|---|
| 1 | ISHARES TR | ACWI | 464288257 | $292.7M | 62.42% | 2,153,477 | SH |
| 2 | KARMAN HLDGS INC | KRMN | 485924104 | $125.0M | 26.67% | 1,562,054 | SH |
| 3 | REVOLUTION MEDICINES INC | RVMD | 76155X100 | $33.5M | 7.14% | 344,091 | SH |
| 4 | TANGO THERAPEUTICS INC | TNGX | 87583X109 | $7.4M | 1.58% | 354,192 | SH |
| 5 | MAZE THERAPEUTICS INC | MAZE | 578784100 | $7.2M | 1.53% | 239,994 | SH |
| 6 | MEDLINE INC | MDLN | 58507V107 | $3.1M | 0.67% | 70,357 | SH |
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-03-31 | 2026-05-05 | $468.9M | 6 | 0001214659-26-005558 |
| 2025-12-31 | 2026-01-27 | $809.8M | 7 | 0001214659-26-000882 |