SEC 13F Intelligence

Managers / Q1 2026

Mass General Brigham, Inc

CIK 0001678378 · 399 REVOLUTION DRIVE, SUITE 612, SOMERVILLE, MA, 02145 · 8572777268

Reported Value
$469M
Q1 2026
Positions
6
Filings on Record
24
2019–present window
Filed
May 5, 2026
original filing

Summary

Mass General Brigham, Inc reported $469M in U.S.-listed holdings across 6 positions for Q1 2026.

The portfolio is heavily concentrated: ACWI alone accounts for 62.4% of reported value.

Compared with Q4 2025, the fund opened 0 new positions and exited 1.

Portfolio Metrics

Turnover
+3.6%
vs prior filed quarter
Largest Position
+62.4%
Ishares Tr

Methodology: turnover is min(value bought, value sold) ÷ average reported value across the two quarters — value-based, so market moves inflate it slightly versus a share-based measure. Concentration and largest position are shares of the filing’s total reported value, options excluded. New/exited counts compare against the prior filed quarter. All figures derive solely from the fund’s 13F filings.

Reported Value by Quarter

13F Reported Value
Q4 ’18: $144MQ4 ’18Q1 ’19: $162MQ2 ’19: $153MQ3 ’19: $436MQ3 ’19Q4 ’19: $290MQ3 ’20: $126MQ4 ’20: $473MQ4 ’20Q1 ’21: $639MQ2 ’21: $410MQ3 ’21: $371MQ3 ’21Q4 ’21: $282MQ1 ’22: $235MQ2 ’22: $214MQ2 ’22Q3 ’22: $192MQ1 ’23: $128,310Q3 ’23: $11MQ3 ’23Q4 ’23: $28MQ1 ’24: $57MQ2 ’24: $21MQ2 ’24Q3 ’24: $44MQ4 ’25: $810MQ1 ’26: $469MQ1 ’26filingsflow.com

Portfolio Composition

By security type
ETP: 62.4%Common Stock: 37.6%
  • ETP · 62.4% · $293M
  • Common Stock · 37.6% · $176M

Quarter-over-Quarter Changes full breakdown →

vs Q4 2025 (amended baseline)

IssuerMoveShare ΔShares nowValue ΔValue now
MDLNMEDLINE INCADDED+44.1K70.4K+$2M$3M
RBRKRUBRIK INCSOLD OUT14.0K0$1M$0
ACWIISHARES TRTRIMMED2.46M2.15M$360M$293M
KRMNKARMAN HLDGS INCHELD+01.56M+$11M$125M
RVMDREVOLUTION MEDICINES INCHELD+0344.1K+$6M$33M
TNGXTANGO THERAPEUTICS INCHELD+0354.2K+$4M$7M
MAZEMAZE THERAPEUTICS INCHELD+0240.0K$3M$7M

Value changes conflate price moves with buying and selling — share changes are the real signal. Share counts are not split-adjusted.

Holdings — Q1 2026

6 positions
#IssuerClass% PortfolioValueShares
1ACWIISHARES TRhistory →MSCI ACWI ETF62.42%$293M2.15M
2KRMNKARMAN HLDGS INChistory →COM26.67%$125M1.56M
3RVMDREVOLUTION MEDICINES INChistory →COM7.14%$33M344.1K
4TNGXTANGO THERAPEUTICS INChistory →COM1.58%$7M354.2K
5MAZEMAZE THERAPEUTICS INChistory →COM1.53%$7M240.0K
6MDLNMEDLINE INCCOM0.67%$3M70.4K

Filing History

QuarterReported ValuePositionsFiledTypeLinks
Q1 2026$469M6May 5, 202613F-HRchanges · EDGAR ↗
Q4 2025$810M7Jan 27, 202613F-HRchanges · EDGAR ↗
Q3 2024$44M5Oct 16, 202413F-HRchanges · EDGAR ↗
Q2 2024$21M4Jul 31, 202413F-HRchanges · EDGAR ↗
Q1 2024$57M5Apr 4, 202413F-HRchanges · EDGAR ↗
Q4 2023$28M2Jan 24, 202413F-HRchanges · EDGAR ↗
Q3 2023$11M2Oct 23, 202313F-HRchanges · EDGAR ↗
Q2 2023Under review7Jul 21, 202313F-HRchanges · EDGAR ↗
Q1 2023$128,3106Apr 5, 202313F-HRchanges · EDGAR ↗
Q4 2022Under review5Jan 19, 202313F-HRchanges · EDGAR ↗
Q3 2022$192M3Oct 19, 202213F-HRchanges · EDGAR ↗
Q2 2022$214M3Jul 27, 202213F-HRchanges · EDGAR ↗
Q1 2022$235M5Apr 15, 202213F-HRchanges · EDGAR ↗
Q4 2021$282M7Jan 19, 202213F-HRchanges · EDGAR ↗
Q3 2021$371M7Oct 8, 202113F-HRchanges · EDGAR ↗
Q2 2021$410M9Jul 19, 202113F-HRchanges · EDGAR ↗
Q1 2021$639M3Apr 12, 202113F-HRchanges · EDGAR ↗
Q4 2020$473M3Feb 8, 202113F-HRchanges · EDGAR ↗
Q3 2020$126M2Oct 23, 202013F-HRchanges · EDGAR ↗
Q4 2019$290M3Jan 15, 202013F-HRchanges · EDGAR ↗
Q3 2019$436M3Oct 30, 201913F-HRchanges · EDGAR ↗
Q2 2019$153M1Jul 29, 201913F-HRchanges · EDGAR ↗
Q1 2019$162M1Apr 18, 201913F-HRchanges · EDGAR ↗
Q4 2018$144M1Jan 30, 201913F-HRchanges · EDGAR ↗

13F filings are due up to 45 days after quarter end, so holdings shown here lag the fund’s current book. Source: original SEC filing on EDGAR ↗.