13F
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MPM BioImpact LLC

13F equity value
$1.3B
Positions
41
Top 10 concentration
49.0%
Quarters / total new picks
19 / 86
13F equity value over time
$0M$647M$1B20192020202120222023202420252026

"13F equity value" = market value of this filer's US-listed long equity positions only. It excludes cash, bonds, non-US and short positions, so it understates a fund's true assets under management — often by a lot.

Not significant Verdict

13F holdings are disclosed ~45 days after quarter-end, and they never reveal when within the quarter a fund actually bought. So any 13F-based summary is structurally late and blurred — this applies to every fund, including this one.

We backtested copying it anyway. Buying this fund's new positions the day each filing went public, over 19 quarters, returned +13.4% per quarter — versus +1.7% per quarter from simply owning every 13F stock. It beat that baseline in only 36.8% of quarters (excess t = 1.29, not statistically significant). Its filings tell you what it bought — not what you should buy.

Avg 2Q excess
+38.9%
t-stat
1.29
Quarterly win rate
37%
Annualized excess
+15.3%
$1 → follow vs universe
$2.45 vs $1.29
Cumulative return: $1 invested in new picks vs universe
1.00 20201231: universe 1.04620210930: universe 0.93920211231: universe 0.79920220331: universe 0.85820220630: universe 0.79420220930: universe 0.85320221231: universe 0.79320230331: universe 0.83520230630: universe 0.80520230930: universe 0.91420231231: universe 0.95520240331: universe 0.97620240630: universe 1.06520240930: universe 1.05620241231: universe 0.98520250331: universe 1.07420250630: universe 1.10820250930: universe 1.24620251231: universe 1.289 20201231: follow 0.95420210930: follow 0.84620211231: follow 0.49420220331: follow 0.61120220630: follow 0.46120220930: follow 0.48720221231: follow 0.52520230331: follow 0.52420230630: follow 0.49420230930: follow 1.67520231231: follow 1.16020240331: follow 1.13020240630: follow 1.70020240930: follow 1.59420241231: follow 1.34320250331: follow 1.94420250630: follow 2.21720250930: follow 2.57020251231: follow 2.453 0.42 1.60 2.78 202020212022202320242025 Follow Universe

Quarterly compounding, invested quarters only · entry 47 days after quarter-end (when 13F data becomes public)

Listed as facts. See the verdict above before treating this as signal.

Top 20 holdings of 41 · 2026 Q1

Ticker Value Weight QoQ
DBVT $109M
8.4%
ADD
CGEM $109M
8.4%
HOLD
AKTS $87M
6.7%
NEW
LQDA $53M
4.1%
HOLD
ALMS $53M
4.1%
HOLD
EWTX $52M
4.0%
HOLD
RVMD $49M
3.8%
HOLD
AGIO $44M
3.4%
HOLD
CORT $40M
3.1%
NEW
TRVI $39M
3.0%
HOLD
DNTH $36M
2.8%
NEW
XENE $34M
2.6%
ADD
MLTX $34M
2.6%
NEW
TVTX $34M
2.6%
NEW
EVMN $33M
2.6%
ADD
CYTK $33M
2.5%
NEW
SNDX $31M
2.4%
HOLD
CNTX $28M
2.2%
HOLD
FBRX $26M
2.0%
NEW
PVLA $26M
2.0%
HOLD

QoQ vs previous quarter's share count · NEW = new position · ADD/TRIM = ±2% shares · HOLD = unchanged.

Listed as facts. See the verdict above before treating this as signal.

New positions in 2026 Q1

ACRSALLOCORTCYTKDNTHFBRXMLTXTVTXVRDNZYME

Method & Limitations

Method: a "new position" = held this quarter, absent last quarter (options excluded; stocks with <50 prior holders excluded to filter spin-off artifacts). Entry 47 days after quarter-end — the first day the public could act on the filing. Benchmark = equal-weighted universe of all 13F-held stocks. Limitations: quarterly snapshots can't see intra-quarter trades; survivorship bias — funds that shut down are absent, which flatters the sample. Statistics, not advice.