Tandem Diabetes Care
TNDM
270 hedge funds and large institutions have $1.51B invested in Tandem Diabetes Care in 2025 Q2 according to their latest regulatory filings, with 40 funds opening new positions, 117 increasing their positions, 70 reducing their positions, and 43 closing their positions.
1,031% more call options, than puts
Call options by funds: $54.4M | Put options by funds: $4.81M
67% more repeat investments, than reductions
Existing positions increased: 117 | Existing positions reduced: 70
11.66% more ownership
Funds ownership: 109.92% → 121.58% (+12%)
8% more capital invested
Capital invested by funds: $1.4B → $1.51B (+$107M)
0% more funds holding in top 10
Funds holding in top 10: 2 → 2 (0)
7% less first-time investments, than exits
New positions opened: 40 | Existing positions closed: 43
2% less funds holding
Funds holding: 275 → 270 (-5)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
OAM
Ophir Asset Management
Sydney,
Australia
|
+$29M |
| 2 |
Goldman Sachs
New York
|
+$23.3M |
| 3 |
Millennium Management
New York
|
+$14.7M |
| 4 |
Two Sigma Investments
New York
|
+$11.7M |
| 5 |
Walleye Capital
New York
|
+$11.2M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
PWAM
Park West Asset Management
San Francisco,
California
|
-$21.5M |
| 2 |
Fidelity Investments
Boston,
Massachusetts
|
-$18.1M |
| 3 |
FAM
Fred Alger Management
New York
|
-$15.6M |
| 4 |
Balyasny Asset Management
Chicago,
Illinois
|
-$10.7M |
| 5 |
KCM
Kingdon Capital Management
New York
|
-$9.49M |
TNDM Hedge Fund Activity: Q2 2025 in Review
270 of the 7,595 institutional investors tracked by Wall St. Rank reported a position in Tandem Diabetes Care (TNDM) for Q2 2025, worth a combined $1.51B — up 7.6% from $1.4B a quarter earlier.
Sellers outnumbered buyers: 43 funds closed out of TNDM and 40 opened new positions — a net loss of 3 holders — while 70 trimmed existing stakes and 117 added.
The largest buyer was Ophir Asset Management, opening a new position worth an estimated $29M. The largest seller was Park West Asset Management, exiting entirely with an estimated $21.5M sold.
- 270 institutional investors held Tandem Diabetes Care (TNDM) as of Q2 2025, down from 275 in Q1 2025.
- Funds reported $1.51B of Tandem Diabetes Care stock for Q2 2025, up 7.6% quarter-over-quarter.
- 40 funds opened new Tandem Diabetes Care positions in Q2 2025 and 43 closed out, a net change of -3 holders.
- The largest Tandem Diabetes Care buyer in Q2 2025 was Ophir Asset Management, an estimated $29M added.
- The largest Tandem Diabetes Care seller in Q2 2025 was Park West Asset Management, an estimated $21.5M sold.
Based on aggregated 13F filings for Q2 2025.