John F. Sheridan is CEO & President at TANDEM DIABETES CARE INC (TNDM). They have made 16 open-market trades across 2 companies since 2006, most recently 2026-08-15.
CIK 0001365369
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.
2 open-market purchases totalling $277K since 2022, against 14 sales. Too few scored purchases to measure a record yet.
| Ticker | Type | Traded | Filed | Price | Value | 7d Stock | 30d Stock | 90d Stock |
|---|---|---|---|---|---|---|---|---|
| TNDM | BUY | 2025-08-11 | 2025-08-11 | $10.23 | $102K | -0.2% | +11.7% | +47.9% |
| TNDM | BUY | 2022-05-09 | 2022-05-10 | $69.90 | $175K | +4.5% | -8.9% | -12.7% |
| TNDM | SELL | 2021-08-06 | 2021-08-10 | $107.90 | $2.9M | +9.2% | +21.6% | +31.5% |
| TNDM | SELL | 2020-10-13 | 2020-10-15 | $121.31 | $3.6M | -5.2% | -21.1% | -22.3% |
| TNDM | SELL | 2020-09-15 | 2020-09-17 | $110.01 | $1.1M | +4.5% | +9.6% | -19.9% |
| TNDM | SELL | 2020-08-03 | 2020-08-04 | $102.20 | $3.4M | -8.1% | +4.1% | +2.8% |
| TNDM | SELL | 2020-02-21 | 2020-02-24 | $87.85 | $5.2M | -5.1% | -29.7% | +3.4% |
| TNDM | SELL · 10b5-1 | 2019-11-25 | 2019-11-26 | $70.00 | $32K | -16.7% | -14.4% | +23.2% |
| TNDM | SELL | 2019-09-06 | 2019-09-09 | $70.03 | $1.3M | -0.1% | -10.4% | -4.7% |
| TNDM | SELL | 2019-02-27 | 2019-02-27 | $62.03 | $1.2M | +6.1% | +3.3% | +6.7% |
| TNDM | SELL | 2019-01-25 | 2019-01-25 | $45.26 | $905K | -4.4% | +10.1% | +36.9% |
| TNDM | SELL | 2018-12-31 | 2019-01-03 | $35.72 | $1.5M | +30.9% | +30.7% | +88.5% |
| TNDM | SELL | 2016-08-01 | 2016-08-03 | $6.52 | $98K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2016-05-02 | 2016-05-02 | $10.61 | $21K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2016-04-22 | 2016-04-22 | $10.00 | $20K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2016-03-07 | 2016-03-09 | $10.01 | $40K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL | 2016-01-04 | 2016-01-05 | $11.47 | $23K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2016-01-04 | 2016-03-09 | $11.47 | $23K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2015-12-01 | 2015-12-02 | $10.14 | $20K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2015-11-02 | 2015-11-03 | $10.00 | $40K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2015-09-14 | 2015-09-16 | $12.51 | $25K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL | 2015-08-05 | 2015-08-07 | $12.45 | $436K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2015-05-01 | 2015-05-01 | $13.72 | $27K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2015-04-01 | 2015-04-03 | $12.47 | $25K | -64.7% | -22.0% | -22.0% |
| TNDM | SELL · 10b5-1 | 2015-03-02 | 2015-03-04 | $11.76 | $24K | -64.7% | -22.0% | -22.0% |
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.