According to recent filings covering the 90 days ending January 10, 2026, the three most significant insider holders at Quest Diagnostics are Director Stephen H Rusckowski (389.60K shares), Ceo And President J. E. Davis (120.48K shares), Executive Vice President & Cfo Mark Guinan (98.98K shares).
| Holder | Position | Shares | Report Date |
|---|---|---|---|
| Stephen H Rusckowski | 389,597 | 08 Mar, 2023 | |
| J. E. Davis | Ceo And President | 120,480 | 28 Nov, 2025 |
| Mark Guinan | Executive Vice President & Cfo | 98,981 | 09 Mar, 2022 |
| Catherine T. Doherty | Evp And Regional Businesses | 68,068 | 07 Mar, 2025 |
| Manner Carrie Eglinton | Svp And Advanced Diagnostics | 48,391 | 09 Mar, 2022 |
| Michael E Prevoznik | Svp & General Counsel | 38,117 | 30 Sep, 2025 |
| Michael J Deppe | Svp And Corp. Controller & Cao | 34,365 | 05 Mar, 2025 |
| Timothy M Ring | 29,507 | 19 May, 2025 | |
| Gary M Pfeiffer | 29,431 | 24 Oct, 2025 | |
| Timothy L Main | 26,297 | 19 May, 2025 | |
| Sam Samad | Executive Vice President & Cfo | 25,741 | 24 Oct, 2025 |
| Gail R Wilensky | 20,506 | 19 May, 2023 | |
| Vicky B Gregg | 17,037 | 28 Nov, 2025 | |
| Patrick Plewman | Svp For Diagnostic Services | 15,333 | 24 Oct, 2025 |
| Denise M Morrison | 10,742 | 19 May, 2025 | |
| Wright Iii Lassiter | 9,044 | 25 Jul, 2025 | |
| Karthik Kuppusamy | Svp And Clinical Solutions | 8,737 | 24 Oct, 2025 |
| Mark E Delaney | Svp & Chief Commercial Officer | 7,530 | 20 Nov, 2025 |
| Tracey Doi | 6,490 | 19 May, 2025 | |
| Helen Torley | 6,260 | 25 May, 2021 | |
| Mark A Gardner | Svp Of Molecular Gen & Oncol | 4,673 | 26 Sep, 2024 |
| Luis Diaz | 4,054 | 19 May, 2025 | |
| Robert B Carter | 2,698 | 24 Oct, 2025 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 25 Nov, 2025 | Vicky B Gregg | Common Stock | D | 1,250 | $191.76 | 17,037 | D | S |
| 25 Nov, 2025 | J. E. Davis | Common Stock | D | 4,747 | $192.97 | 120,480 | D | S |
| 25 Nov, 2025 | J. E. Davis | Common Stock | D | 9,342 | $191.59 | 166,231 | D | S |
| 25 Nov, 2025 | J. E. Davis | Common Stock | D | 41,004 | $192.27 | 125,227 | D | S |
| 25 Nov, 2025 | J. E. Davis | Common Stock | A | 55,093 | $95.80 | 175,573 | D | M |
| 18 Nov, 2025 | Mark E Delaney | Common Stock | A | 7,846 | $144.47 | 15,376 | D | M |
| 18 Nov, 2025 | Mark E Delaney | Common Stock | A | 100 | $143.33 | 15,476 | D | M |
| 18 Nov, 2025 | Mark E Delaney | Common Stock | D | 7,946 | $187.35 | 7,530 | D | S |
| 05 Nov, 2025 | J. E. Davis | Common Stock | D | 7,143 | $175.57 | 120,480 | D | F |
| 22 Oct, 2025 | Gary M Pfeiffer | Common Stock | D | 1,482 | $182.40 | 29,431 | D | S |
| 21 Oct, 2025 | Robert B Carter | Common Stock | A | 6 | $189.09 | 2,698 | D | A |
| 21 Oct, 2025 | Patrick Plewman | Common Stock | A | 46 | $189.08 | 15,333 | D | A |
| 21 Oct, 2025 | Vicky B Gregg | Common Stock | A | 70 | $189.08 | 18,287 | D | A |
| 21 Oct, 2025 | Sam Samad | Common Stock | A | 68 | $189.08 | 25,741 | D | A |
| 21 Oct, 2025 | Karthik Kuppusamy | Common Stock | A | 15 | $189.08 | 8,379 | D | A |
| 21 Oct, 2025 | Mark E Delaney | Common Stock | A | 15 | $189.08 | 7,530 | D | A |
| 26 Sep, 2025 | Michael E Prevoznik | Common Stock | D | 83 | $187.22 | 38,261 | D | S |
| 26 Sep, 2025 | Michael E Prevoznik | Common Stock | D | 144 | $188.66 | 38,117 | D | S |
| 26 Sep, 2025 | Michael E Prevoznik | - | - | 38,344 | D | |||
| 26 Sep, 2025 | Michael E Prevoznik | Common Stock | A | 227 | $103.57 | 38,344 | D | M |