Tandem Diabetes Care Inc insider trading
Every open-market purchase and sale by Tandem Diabetes Care Inc's officers, directors and largest shareholders since November 4, 2021, and what the share price did next.
| Date | Insider | Trade | Shares | Price | Value | 1M after | 3M after | 6M after |
|---|
Does following Tandem Diabetes Care Inc’s insiders pay?
From December 15, 2014 to August 11, 2025, 16 insiders reported 26 open-market purchases and 51 sales not made under a pre-set plan in Tandem Diabetes Care Inc. Twelve months after each purchase was reported, the shares were +12.1% against the S&P 500 on average (median +26.4%), over 18 purchases with a full year of prices; 61% beat the index. After sales, the shares moved −15.7% against the index over 12 months (a negative figure means selling was the right call). That rests on fewer than 20 purchases, too few to read much into. Buying each purchase the day after it was reported, an equal amount each, held 12 months or until that insider reported a sale, would have turned $10,000 on December 16, 2014 into $1,725 by November 2, 2026, −13.8% a year. It held shares 63% of the time; the S&P 500 on those same days, with Treasury bills otherwise, made $31,840 (+10.3% a year), and held throughout $46,646 (+13.9%).
| Insider | Role | Purchases | 12 months after their purchases | Beat the S&P 500 | Sales | 12 months after their sales | Latest report |
|---|---|---|---|---|---|---|---|
| Blickenstaff Kim D | Executive Chairman | 3 | — | — | 23 | −9.8% (23) | November 22, 2024 |
| Allen Dick | Director | 6 | −8.9% (4) | 50% | 6 | −2.8% (6) | June 3, 2024 |
| Berger David B | EVP & Chief Operating Officer | 0 | — | — | 8 | −39.0% (8) | March 7, 2023 |
| Sheridan John F | PRESIDENT & CEO | 2 | +13.3% (2) | 50% | 5 | −38.0% (5) | August 11, 2025 |
| Greene Howard E Jr | Director | 1 | — | — | 4 | +13.6% (4) | August 6, 2019 |
| Vosseller Leigh | EVP & CHIEF FINANCIAL OFFICER | 4 | +19.8% (4) | 75% | 0 | — | August 11, 2025 |
| Twomey Christopher J | Director | 1 | — | — | 2 | −35.2% (2) | May 10, 2022 |
| Howell Peyton R | Director | 2 | −7.1% (2) | 50% | 0 | — | May 19, 2023 |
| Mcgroddy-Goetz Kathleen | Director | 1 | +64.7% (1) | 100% | 1 | −54.3% (1) | September 19, 2023 |
| Valencia Richard P. | Director | 2 | +59.6% (2) | 100% | 0 | — | November 7, 2018 |
| Cahill Edward L | Director | 0 | — | — | 1 | +48.4% (1) | August 14, 2019 |
| Hansen Brian B | EVP & CHIEF COMMERCIAL OFFICER | 0 | — | — | 1 | −32.9% (1) | August 4, 2020 |
| Hansen Shannon Marie | Chief Legal Officer | 1 | +26.4% (1) | 100% | 0 | — | November 13, 2023 |
| Kyrillos Jean-Claude | EVP & Chief Operating Officer | 1 | −4.9% (1) | 0% | 0 | — | March 11, 2025 |
| Novara Mark David | EVP & CHIEF COMMERCIAL OFFICER | 1 | −43.4% (1) | 0% | 0 | — | November 19, 2024 |
| Roeder Douglas A | Director | 1 | — | — | 0 | — | February 13, 2018 |
When several insiders traded Tandem Diabetes Care Inc
Months when 2 or more insiders became net buyers, or 3 or more net sellers, of Tandem Diabetes Care Inc in reports dated in the 91 days before the month end, and how the stock did against the S&P 500 from that month end. After the 3 buying crowds with six months of prices, it averaged +63.6% against the index. After 6 selling crowds, +11.8%. One company's history is too short to judge by; the test across every company is the better guide.
| Month | Crowd | 3 months on, vs S&P 500 | 6 months | 12 months |
|---|---|---|---|---|
| August 29, 2025 | 2 buying | +61.7% | +83.7% | +50.7% |
| November 30, 2023 | 4 buying | +41.2% | +140.3% | +26.6% |
| May 31, 2023 | 3 buying | +1.4% | −33.3% | +69.1% |
| May 31, 2022 | 4 selling | −29.5% | −37.9% | −67.9% |
| May 28, 2021 | 3 selling | +21.6% | +41.9% | −17.2% |
| August 31, 2020 | 3 selling | −20.8% | −30.3% | −31.7% |
| September 30, 2019 | 3 selling | −9.0% | +21.3% | +76.8% |
| March 29, 2019 | 4 selling | −2.6% | −13.0% | +12.6% |
| November 30, 2018 | 3 selling | +70.9% | +89.1% | +71.2% |