Mass General Brigham, Inc — 13F Holdings & Portfolio
CIK 1678378 · latest 13F-HR filed 2026-08-07
Mass General Brigham, Inc manages $361.1M in 13F-reported U.S. long-equity assets across 6 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are ACWI (54.76%), KRMN (21.60%), RVMD (17.85%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 0 new positions, exited 0, added to 2, and trimmed 3.
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.
SUITE 612
SOMERVILLE, MA 02145
$361.1M
Long-equity book
6
Distinct positions
2026-06-30
Filed 2026-08-07
+0 / −0 / ↑2 / ↓3
vs 2026-03-31
| Name | Title / Status | Ownership | Type |
|---|
Top Adds (vs prior quarter)
- REVOLUTION MEDICINES INC$31.0M +92.6%
- TANGO THERAPEUTICS INC$3.7M +49.4%
Top Trims
- ISHARES TR-$95.0M -32.4%
- KARMAN HLDGS INC-$47.1M -37.6%
- MEDLINE INC-$432.7K -13.8%
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 | $197.7M | 54.76% | 1,259,657 | SH |
| 2 | KARMAN HLDGS INC | KRMN | 485924104 | $78.0M | 21.60% | 1,562,054 | SH |
| 3 | REVOLUTION MEDICINES INC | RVMD | 76155X100 | $64.4M | 17.85% | 344,091 | SH |
| 4 | TANGO THERAPEUTICS INC | TNGX | 87583X109 | $11.1M | 3.07% | 354,192 | SH |
| 5 | MAZE THERAPEUTICS INC | MAZE | 578784100 | $7.2M | 1.98% | 239,994 | SH |
| 6 | MEDLINE INC | MDLN | 58507V107 | $2.7M | 0.75% | 68,413 | SH |
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-06-30 | 2026-08-07 | $361.1M | 6 | 0001214659-26-009752 |
| 2026-03-31 | 2026-05-05 | $468.9M | 6 | 0001214659-26-005558 |
| 2025-12-31 | 2026-01-27 | $809.8M | 7 | 0001214659-26-000882 |