| Insider | Role | Shares | Value | Buys | Sells |
|---|---|---|---|---|---|
| Date | Ticker | Insider | Role | Type | Shares | Price | Value | Chg% | SEC |
|---|---|---|---|---|---|---|---|---|---|
| Insider | Role | Shares | Value | Buys | Sells |
|---|---|---|---|---|---|
| Date | Ticker | Insider | Role | Type | Shares | Price | Value | Chg% | SEC |
|---|---|---|---|---|---|---|---|---|---|
Director | EVP, Chief Financial Officer | Executive VP and CFO
2 companies
Mark Stolper is EVP, Chief Financial Officer at RDNT and has filed Form 4s across 2 companies. Mark Stolper's net worth is not public. Form 4 filings only show shares in the companies where this person is an insider; those holdings are worth an estimated $8.9M at current prices.
The biggest single holding is RDNT (~$8.9M) as EVP, Chief Financial Officer. The RDNT filings lean toward selling, a net 240,304 shares.
Mark Stolper has 38 Form 4 filings on record from January 2015 to July 2026, across 3 companies: Director at The Oncology Institute (TOIIW), 2026; EVP, Chief Financial Officer at RadNet (RDNT), 2015–2026; Director at Coherus Oncology (CHRS), 2021–2024.
The 52 reported transactions were 22 option or other derivative awards, 10 open-market sales, 8 stock awards and 4 gifts, plus smaller numbers of other types.
Counted by filing, the open-market trades come to no purchases and 10 sales worth about $5.7M.
The largest open-market sale was 35,000 shares of RDNT at an average $73.89 on September 16, 2025, about $2.6M. Twelve months later RDNT was up 2%.
Neither of the two sales since April 2023 was marked as made under a Rule 10b5-1 trading plan.
| Date | Ticker | Role | Type | Shares | Price | Value | Chg% | 3M | 12M | SEC |
|---|---|---|---|---|---|---|---|---|---|---|
| Sep 16, 2025 | RDNT Radnet, Inc. | EVP, Chief Financial Officer | Sell | 35,000 | $73.89 | $2,586,150.00 | -34.0% | -2.4% | +1.9% | |
| Jun 10, 2024 | RDNT Radnet, Inc. | EVP, Chief Financial Officer | Sell | 25,000 | $61.27 | $1,531,750.00 | -23.7% | -1.0% | -3.6% | |
| Aug 15, 2019 | RDNT Radnet, Inc. | Executive VP and CFO | Sell | 20,703 | $15.15 | $313,650.45 | -18.3% | - | - | |
| Mar 18, 2019 | RDNT Radnet, Inc. | Executive VP and CFO | Sell | 15,000 | $14.99 | $224,895.00 | -11.7% | - | - | |
| Mar 20, 2018 | RDNT Radnet, Inc. | Executive VP and CFO | Sell | 15,000 | $13.19 | $197,850.00 | -10.3% | - | - | |
| Aug 30, 2017 | RDNT Radnet, Inc. | Executive VP and CFO | Sell | 10,000 | $10.19 | $101,900.00 | -6.4% | - | - | |
| May 24, 2017 | RDNT Radnet, Inc. | Executive VP and CFO | Sell | 15,000 | $7.33 | $109,950.00 | -8.8% | - | - | |
| Aug 12, 2016 | RDNT Radnet, Inc. | Executive VP and CFO | Sell | 35,414 | $6.25 | $221,337.50 | -17.2% | - | - | |
| Dec 3, 2015 | RDNT Radnet, Inc. | Executive VP and CFO | Sell | 19,187 | $6.18 | $118,575.66 | -10.1% | - | - | |
| May 20, 2015 | RDNT Radnet, Inc. | Executive VP and CFO | Sell | 50,000 | $6.86 | $343,000.00 | -20.9% | - | - |