Tandem Diabetes Care
TNDM
275 hedge funds and large institutions have $1.4B invested in Tandem Diabetes Care in 2025 Q1 according to their latest regulatory filings, with 39 funds opening new positions, 107 increasing their positions, 86 reducing their positions, and 78 closing their positions.
1,027% more call options, than puts
Call options by funds: $61.6M | Put options by funds: $5.47M
24% more repeat investments, than reductions
Existing positions increased: 107 | Existing positions reduced: 86
0.15% more ownership
Funds ownership: 109.77% → 109.92% (+0.15%)
13% less funds holding
Funds holding: 316 → 275 (-41)
46% less capital invested
Capital invested by funds: $2.6B → $1.4B (-$1.2B)
50% less first-time investments, than exits
New positions opened: 39 | Existing positions closed: 78
60% less funds holding in top 10
Funds holding in top 10: 5 → 2 (-3)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
SC
Sessa Capital
New York
|
+$131M |
| 2 |
HRCM
Hood River Capital Management
Palm Beach Gardens,
Florida
|
+$30.3M |
| 3 |
Balyasny Asset Management
Chicago,
Illinois
|
+$22.5M |
| 4 |
GKIM
GW&K Investment Management
Boston,
Massachusetts
|
+$21.7M |
| 5 |
PIM
Paradice Investment Management
Denver,
Colorado
|
+$20.3M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
GGHC
Gilder Gagnon Howe & Co
New York
|
-$33.6M |
| 2 |
BG
Bellevue Group
Kuesnacht,
Switzerland
|
-$28.2M |
| 3 |
CC
Chicago Capital
Chicago,
Illinois
|
-$27.8M |
| 4 |
Capital International Investors
Los Angeles,
California
|
-$25.9M |
| 5 |
Marshall Wace
London,
United Kingdom
|
-$25.8M |
TNDM Hedge Fund Activity: Q1 2025 in Review
275 of the 7,459 institutional investors tracked by Wall St. Rank reported a position in Tandem Diabetes Care (TNDM) for Q1 2025, worth a combined $1.4B — down 46% from $2.6B a quarter earlier.
Sellers outnumbered buyers: 78 funds closed out of TNDM and 39 opened new positions — a net loss of 39 holders — while 86 trimmed existing stakes and 107 added.
The largest buyer was Sessa Capital, opening a new position worth an estimated $131M. The largest seller was Gilder Gagnon Howe & Co, exiting entirely with an estimated $33.6M sold.
- 275 institutional investors held Tandem Diabetes Care (TNDM) as of Q1 2025, down from 316 in Q4 2024.
- Funds reported $1.4B of Tandem Diabetes Care stock for Q1 2025, down 46% quarter-over-quarter.
- 39 funds opened new Tandem Diabetes Care positions in Q1 2025 and 78 closed out, a net change of -39 holders.
- The largest Tandem Diabetes Care buyer in Q1 2025 was Sessa Capital, an estimated $131M added.
- The largest Tandem Diabetes Care seller in Q1 2025 was Gilder Gagnon Howe & Co, an estimated $33.6M sold.
Based on aggregated 13F filings for Q1 2025.