Leigh Vosseller is CFO & VP at TANDEM DIABETES CARE INC (TNDM). They have made 19 open-market trades across 1 company since 2019, most recently 2026-08-15.
CIK 0001726322
Unrated. We grade insiders only on stock they chose to buy on the open market. Grants, option exercises and vesting say nothing about timing, so they don't count — which is why someone can file often and still have no grade. It isn't a bad sign: unrated buys beat every graded tier below A.
4 open-market purchases totalling $778K since 2022, against 15 sales. Too few scored purchases to measure a record yet.
| Ticker | Shares | Value |
|---|---|---|
| TNDM | 52,040 | $845K |
Shares reported on the most recent Form 4, priced at the 2026-08-18 close.
| Ticker | Type | Traded | Filed | Price | Value | 7d Stock | 30d Stock | 90d Stock |
|---|---|---|---|---|---|---|---|---|
| TNDM | BUY | 2025-08-08 | 2025-08-11 | $10.89 | $299K | -0.2% | +11.7% | +47.9% |
| TNDM | BUY | 2023-11-08 | 2023-11-13 | $15.39 | $95K | +20.1% | +60.2% | +51.3% |
| TNDM | BUY | 2023-05-12 | 2023-05-16 | $32.77 | $198K | -11.3% | -9.1% | -3.6% |
| TNDM | BUY | 2022-05-06 | 2022-05-10 | $74.61 | $187K | +4.5% | -8.9% | -12.7% |
| TNDM | SELL | 2021-11-03 | 2021-11-05 | $140.05 | $1.4M | +7.9% | -0.8% | -12.0% |
| TNDM | SELL | 2021-10-12 | 2021-10-14 | $132.55 | $2.7M | -1.7% | +3.4% | -3.4% |
| TNDM | SELL | 2021-09-15 | 2021-09-17 | $125.00 | $1.3M | -0.4% | +2.0% | +18.7% |
| TNDM | SELL | 2021-09-13 | 2021-09-15 | $120.75 | $1.2M | -2.4% | +1.0% | +5.3% |
| TNDM | SELL | 2020-10-13 | 2020-10-15 | $120.87 | $2.4M | -5.2% | -21.1% | -22.3% |
| TNDM | SELL | 2020-07-31 | 2020-08-04 | $110.03 | $1.1M | -8.1% | +4.1% | +2.8% |
| TNDM | SELL | 2020-07-06 | 2020-07-07 | $105.04 | $1.1M | +1.0% | +3.3% | +11.3% |
| TNDM | SELL | 2020-06-30 | 2020-07-02 | $97.74 | $3.9M | -3.2% | +2.6% | +10.5% |
| TNDM | SELL | 2020-05-07 | 2020-05-08 | $90.07 | $1.8M | -0.1% | -3.8% | +23.8% |
| TNDM | SELL | 2020-02-10 | 2020-02-12 | $80.05 | $1.3M | -3.5% | -29.1% | +7.2% |
| TNDM | SELL | 2020-01-29 | 2020-01-31 | $75.92 | $1.5M | +8.1% | +5.1% | +6.4% |
| TNDM | SELL | 2019-11-25 | 2019-11-26 | $70.35 | $704K | -16.7% | -14.4% | +23.2% |
| TNDM | SELL | 2019-11-18 | 2019-11-18 | $65.41 | $654K | +9.2% | +0.6% | +41.7% |
| TNDM | SELL | 2019-05-16 | 2019-05-17 | $70.45 | $705K | +6.3% | -1.8% | -12.2% |
| TNDM | SELL | 2019-05-03 | 2019-05-06 | $65.14 | $651K | +5.0% | +6.7% | -7.7% |
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.