Y-mAbs Therapeutics
YMAB
YMAB was delisted on the 15th of September, 2025.
97 hedge funds and large institutions have $749M invested in Y-mAbs Therapeutics in 2021 Q3 according to their latest regulatory filings, with 10 funds opening new positions, 40 increasing their positions, 30 reducing their positions, and 13 closing their positions.
33% more repeat investments, than reductions
Existing positions increased: 40 | Existing positions reduced: 30
0.2% more ownership
Funds ownership: 60.02% → 60.22% (+0.2%)
0% more funds holding in top 10
Funds holding in top 10: 2 → 2 (0)
3% less funds holding
Funds holding: 100 → 97 (-3)
16% less capital invested
Capital invested by funds: $887M → $749M (-$138M)
23% less first-time investments, than exits
New positions opened: 10 | Existing positions closed: 13
100% less call options, than puts
Call options by funds: $0 | Put options by funds: $665K
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
PCH
Polar Capital Holdings
London,
United Kingdom
|
+$17.9M |
| 2 |
Artisan Partners
Milwaukee,
Wisconsin
|
+$11.7M |
| 3 |
Vanguard Group
Malvern,
Pennsylvania
|
+$5.32M |
| 4 |
Dimensional Fund Advisors
Austin,
Texas
|
+$3.96M |
| 5 |
SCM
Soleus Capital Management
Greenwich,
Connecticut
|
+$3.83M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
FLAM
First Light Asset Management
Edina,
Minnesota
|
-$11.7M |
| 2 |
CAM
Cormorant Asset Management
Boston,
Massachusetts
|
-$9.45M |
| 3 |
TCM
Tekla Capital Management
Boston,
Massachusetts
|
-$6.69M |
| 4 |
Wellington Management Group
Boston,
Massachusetts
|
-$5.37M |
| 5 |
ACM
Ashford Capital Management
Wilmington,
Delaware
|
-$4.14M |
YMAB Hedge Fund Activity: Q3 2021 in Review
97 of the 5,729 institutional investors tracked by Wall St. Rank reported a position in Y-mAbs Therapeutics (YMAB) for Q3 2021, worth a combined $749M — down 16% from $887M a quarter earlier.
Sellers outnumbered buyers: 13 funds closed out of YMAB and 10 opened new positions — a net loss of 3 holders — while 30 trimmed existing stakes and 40 added.
The largest buyer was Polar Capital Holdings, adding an estimated $17.9M. The largest seller was First Light Asset Management, cutting an estimated $11.7M.
- 97 institutional investors held Y-mAbs Therapeutics (YMAB) as of Q3 2021, down from 100 in Q2 2021.
- Funds reported $749M of Y-mAbs Therapeutics stock for Q3 2021, down 16% quarter-over-quarter.
- 10 funds opened new Y-mAbs Therapeutics positions in Q3 2021 and 13 closed out, a net change of -3 holders.
- The largest Y-mAbs Therapeutics buyer in Q3 2021 was Polar Capital Holdings, an estimated $17.9M added.
- The largest Y-mAbs Therapeutics seller in Q3 2021 was First Light Asset Management, an estimated $11.7M sold.
Based on aggregated 13F filings for Q3 2021.