Tandem Diabetes Care
TNDM · NASDAQ
$16.52+$0.14 (+0.85%)TodayMarket closed ·
Prev close $16.38
Who owns TNDM
Largest institutional holders, from their latest 13F filings
The 10 largest institutions hold 55.2% of TNDM’s shares.
- BlackRock Institutional Trust Company, N.A.14.8%
- Sessa Capital7.4%
- Vanguard Portfolio Management, LLC6.3%
- First Light Asset Management, LLC4.9%
- Next 6 largest institutions21.7%
- All other shareholders44.8%
| Holder | Shares | % of shares |
|---|---|---|
| BlackRock Institutional Trust Company, N.A. | 10.15M | 14.80% |
| Sessa Capital | 5.10M | 7.44% |
| Vanguard Portfolio Management, LLC | 4.30M | 6.27% |
| First Light Asset Management, LLC | 3.38M | 4.94% |
| Vanguard Capital Management, LLC | 3.10M | 4.52% |
| State Street Investment Management (US) | 2.85M | 4.16% |
| GW&K Investment Management, LLC | 2.57M | 3.75% |
| Jennison Associates LLC | 2.33M | 3.40% |
| Paradice Investment Management LLC | 2.02M | 2.95% |
| Jacobs Levy Equity Management, Inc. | 2.01M | 2.93% |
Largest mutual fund holders
| Holder | Shares | % of shares |
|---|---|---|
| iShares Core S&P Small-Cap ETF | 4.17M | 6.09% |
| Vanguard Total Stock Market Index Fund | 2.19M | 3.19% |
| iShares Russell 2000 ETF | 1.81M | 2.64% |
| Vanguard Small-Cap Index Fund | 1.57M | 2.29% |
| Statens Pensjonsfond Utland | 983.19K | 1.43% |
Insider trades
Form 4 filings by officers, directors and large holders
Insiders made no open-market buys or sales of TNDM in the last 6 months.
| Insider | Type | Shares | Value |
|---|---|---|---|
| Vosseller Leigh | Option exercise | 2.62K | — |
| Vosseller Leigh | Option exercise | 1.50K | — |
| Vosseller Leigh | Tax withholding | 942 | $21.40K |
| Vosseller Leigh | Option exercise | 2.62K | — |
| Vosseller Leigh | Tax withholding | 537 | $12.20K |
| Vosseller Leigh | Option exercise | 1.50K | — |
| Morrison Susan | Option exercise | 1.73K | — |
| Morrison Susan | Option exercise | 1.10K | — |
| Morrison Susan | Tax withholding | 495 | $11.25K |
| Morrison Susan | Option exercise | 1.73K | — |
Congressional trades
Disclosed by members of Congress over the last 12 months
| Member | Type | Amount | Traded |
|---|---|---|---|
| Gilbert CisnerosHouse | Purchase | $1K–$15K | Sep 29, 2026 |
Short interest
Settled Sep 30, 2026
- Shares short
- 13.37M
- Days to cover
- 5.25
- % of shares outstanding
- 19.51%
- Average daily volume
- 2.55M
- Change since last report
- +7.2%
Information on this page is provided for informational purposes only and is not a recommendation to buy, sell or hold any security. Investing involves risk, including possible loss of principal. Market data is delayed at least 15 minutes and is provided without warranty. Analyst ratings, price targets and company data come from third-party sources. Past performance does not guarantee future results.