MR
| Investor | Type | Est. change | Change | Δ Own | Date | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Nextech Invest, Ltd.
· Exited
Change
−483K
Δ Own
−100.0%
Date
Q1 2026
|
Nextech Invest, Ltd. | Exited· Q1 2026 | – | −483K | −100.0% | Q1 2026 | |||||
|
Bain Capital Life Sciences Investors, LLC
· Exited
Change
−347K
Δ Own
−100.0%
Date
Q1 2026
|
Bain Capital Life Sciences Investors, LLC | Exited· Q1 2026 | – | −347K | −100.0% | Q1 2026 | |||||
|
Rock Springs Capital Management LP
· Exited
Change
−153K
Δ Own
−100.0%
Date
Q1 2026
|
Rock Springs Capital Management LP | Exited· Q1 2026 | – | −153K | −100.0% | Q1 2026 | |||||
|
Knott David M Jr
· Exited
Change
−112K
Δ Own
−100.0%
Date
Q1 2026
|
Knott David M Jr | Exited· Q1 2026 | – | −112K | −100.0% | Q1 2026 | |||||
|
Acadian Asset Management LLC
· Exited
Change
−111K
Δ Own
−100.0%
Date
Q1 2026
|
Acadian Asset Management LLC | Exited· Q1 2026 | – | −111K | −100.0% | Q1 2026 | |||||
|
Affinity Asset Advisors, LLC
· Exited
Change
−100K
Δ Own
−100.0%
Date
Q1 2026
|
Affinity Asset Advisors, LLC | Exited· Q1 2026 | – | −100K | −100.0% | Q1 2026 | |||||
|
BlackRock
· Exited
Change
−69K
Δ Own
−100.0%
Date
Q1 2026
|
BlackRock | Exited· Q1 2026 | – | −69K | −100.0% | Q1 2026 | |||||
|
Bank of America Corp
· Exited
Change
−66K
Δ Own
−100.0%
Date
Q1 2026
|
Bank of America Corp | Exited· Q1 2026 | – | −66K | −100.0% | Q1 2026 | |||||
|
Millennium Management LLC
· Exited
Change
−63K
Δ Own
−100.0%
Date
Q1 2026
|
Millennium Management LLC | Exited· Q1 2026 | – | −63K | −100.0% | Q1 2026 | |||||
|
Groupe la Francaise
· Exited
Change
−61K
Δ Own
−100.0%
Date
Q1 2026
|
Groupe la Francaise | Exited· Q1 2026 | – | −61K | −100.0% | Q1 2026 | |||||
|
Rangeley Capital, LLC
· Exited
Change
−57K
Δ Own
−100.0%
Date
Q1 2026
|
Rangeley Capital, LLC | Exited· Q1 2026 | – | −57K | −100.0% | Q1 2026 | |||||
|
Gabelli Funds LLC
· Exited
Change
−47K
Δ Own
−100.0%
Date
Q1 2026
|
Gabelli Funds LLC | Exited· Q1 2026 | – | −47K | −100.0% | Q1 2026 | |||||
|
Geode
· Exited
Change
−44K
Δ Own
−100.0%
Date
Q1 2026
|
Geode | Exited· Q1 2026 | – | −44K | −100.0% | Q1 2026 | |||||
|
Credit Industriel Et Commercial
· Exited
Change
−41K
Δ Own
−100.0%
Date
Q1 2026
|
Credit Industriel Et Commercial | Exited· Q1 2026 | – | −41K | −100.0% | Q1 2026 | |||||
|
AQR Capital Management LLC
· Exited
Change
−37K
Δ Own
−100.0%
Date
Q1 2026
|
AQR Capital Management LLC | Exited· Q1 2026 | – | −37K | −100.0% | Q1 2026 | |||||
49 reporting institutions disclosed MRSN position changes in the Q1 2026 snapshot.
For each manager, WhoBought compares accepted consecutive 13F share counts. Share change is current shares minus prior shares. Estimated dollar change is that signed share change multiplied by the split-adjusted quarter-mean close. The activity table on this page uses Q1 2026.
An investor crossing 5% of a share class generally files Schedule 13D for activist intent or Schedule 13G for a passive position. The technical form names appear here rather than in the activity rows.
Ownership and institutional activity come from SEC Form 13F filings. Insider activity comes from SEC Form 4, and large-shareholder activity from SEC Schedules 13D and 13G. FMP supplies price data only. Company logos use the local verified Parqet cache with one shared fallback.
Form 13F is a quarterly disclosure and is normally filed after the quarter ends. Every ownership and activity value therefore names its represented period; it is not presented as a live position.
A muted dash marks a missing table value. It means the filing omitted the value, comparable data is unavailable, or no prior position exists for comparison.