Insiders / Blackford Quentin S.
Blackford Quentin S.
CIK 1612451personinsider
Companies
2
First seen
Feb 26, 2026
Last activity
Jun 12, 2026
Companies
| Company | Shares held | Latest |
|---|---|---|
| Alphatec Holdings, Inc. · ATEC | 600,381 | — |
| iRhythm Holdings, Inc. · IRTC | 204,333 | — |
All securities held
2 positions · latest reported per filing
| Company | Security | Shares |
|---|---|---|
| Alphatec Holdings, Inc. | Common Stock | 600,381 |
| iRhythm Holdings, Inc. | Common Stock | 204,333 |
Activity
InsidersInstitutions
This person's insider trades (Form 4), across every company.| Date | Action | Company | Value | Shares Δ | Position after | Impact |
|---|---|---|---|---|---|---|
| Feb 25, 2026 | Sell | IRTC iRhythm Holdings, Inc. Common Stock | $3.46M | -26K -12.07% | 186,126 0.56% of shares | medium |
| Mar 2, 2026 | Sell | IRTC iRhythm Holdings, Inc. Common Stock | $696.6K | -5K -2.59% | 204,155 0.62% of shares | medium |
| Mar 2, 2026 | Sell | IRTC iRhythm Holdings, Inc. Common Stock | $558.3K | -4K -1.99% | 213,621 0.65% of shares | medium |
| Mar 2, 2026 | Sell | IRTC iRhythm Holdings, Inc. Common Stock | $519.3K | -4K -1.89% | 209,578 0.64% of shares | medium |
| May 29, 2026 | Grant | IRTC iRhythm Holdings, Inc. Common Stock | $17.2K | +178 +0.09% | 204,333 0.62% of shares | low |
| Jun 10, 2026 | Grant | ATEC Alphatec Holdings, Inc. Common Stock | $0 | +32K +5.63% | 600,381 0.39% of shares | low |
| Feb 25, 2026 | Grant | IRTC iRhythm Holdings, Inc. Common Stock | $0 | +32K +17.11% | 217,968 0.66% of shares | low |
| Feb 24, 2026 | Grant | IRTC iRhythm Holdings, Inc. Common Stock | $0 | +47K +28.30% | 211,666 0.64% of shares | low |