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Quest Diagnostics DGX

Quest Diagnostics is the 346th largest S&P 500 company by market cap, worth $26.6 billion. 11 directors have filed with the SEC in the last 12 months (who counts), 1 of them an executive. 7 other officers are on file. At 30 Jun 2026, Vanguard was its largest institutional holder, with 13.2% of the company.

CEO
J. E. Davis
Sector
Health Care
Sub-industry
Health Care Services
Headquarters
Secaucus, New Jersey
Founded
1967
More
Wikipedia
Market cap
$26.6B
346th largest, 23 Oct 2026 close
Revenue
$11.0B
Fiscal year 2025
Price to sales
2.4
Market cap over revenue
Employees
57,000
10-K, 31 Dec 2025
Market cap per employee
$467K
Market cap over employees
Connections
6
S&P 500 companies sharing a director or officer

Largest institutional holders

Each fund group's share of Quest Diagnostics. Where a company has several share classes, the share is of its total value.

13F filings for the quarter to 30 Jun 2026

These five hold 35.7% of Quest Diagnostics.

Source: SEC Form 13F data sets, SEC XBRL shares outstanding · All holders

Board and officers

5 people here also hold roles at other S&P 500 companies.

Roles filed up to 30 Sep 2026

NameTitle
Directors (11)
J. E. DavisCEO and PresidentCEO and President
Robert B. CarterDirectorDirector
Luis DiazDirectorDirector
Tracey DoiDirectorAlso at PentairDirector
Vicky B. GreggDirectorDirector
Wright Lassiter IIIDirectorAlso at FortiveDirector
Timothy L. MainDirectorDirector
Denise M. MorrisonDirectorAlso at MetLife and VisaDirector
Gary M. PfeifferDirectorDirector
Timothy M. RingDirectorAlso at Becton DickinsonDirector
Timothy C. WentworthDirectorDirector
Officers (7)
Sam SamadExecutive Vice President & CFOAlso at Idexx LaboratoriesLast filed 27 Jul 2026Executive Vice President & CFO
Mark E. DelaneySVP & Chief Commercial OfficerLast filed 29 Jul 2026SVP & Chief Commercial Officer
Michael J. DeppeSVP, Corp. Controller & CAOLast filed 6 Mar 2026SVP, Corp. Controller & CAO
Catherine T. DohertyEVP, Regional BusinessesLast filed 6 Mar 2026EVP, Regional Businesses
Karthik KuppusamySVP, Clinical SolutionsLast filed 27 Jul 2026SVP, Clinical Solutions
Patrick PlewmanSVP for Diagnostic ServicesLast filed 27 Jul 2026SVP for Diagnostic Services
Michael E. PrevoznikSVP & General CounselLast filed 31 Aug 2026SVP & General Counsel

Source: SEC insider filings (Forms 3, 4 and 5), Quest Diagnostics' Form 4 filings · All directors and officers

Companies that share people with Quest Diagnostics

Each person's title here, then at the other company.

  • Becton Dickinson BDX
    • Timothy M. Ring: Director here, Director there
  • Fortive FTV
    • Wright Lassiter III: Director here, Director there
  • Idexx Laboratories IDXX
    • Sam Samad: Executive Vice President & CFO here, Director there
  • MetLife MET
    • Denise M. Morrison: Director here, Director there
  • Pentair PNR
    • Tracey Doi: Director here, Director there
  • Visa V
    • Denise M. Morrison: Director here, Director there

Source: SEC insider filings · See the whole network

Quest Diagnostics' market cap since December 2008

Weekly, up to 23 Oct 2026

Show equal percentage changes as equal steps.
201020122014201620182020202220242026$26.6B

Source: Yahoo Finance closing prices, SEC XBRL shares outstanding

Workforce

Headcount at 31 Dec 2025

Employees
57,000
As of December 31, 2025, we have nearly 57,000 employees globally (including LifeLabs’ approximately 6,800), of whom approximately 46,000 are full-time and the remainder are part-time or on-call.
Quest Diagnostics Form 10-K

Source: Quest Diagnostics Form 10-K

Insider trades

Open-market buys and sales by directors and officers. Grants, option exercises and shares withheld for tax are left out.

Trades from 30 Sep 2025 to 30 Sep 2026

Directors and officers sold $37.3 million of stock in 22 sales and made no open-market purchases in the 12 months to 30 Sep 2026.

DatePersonTitleTypeSharesValue
1 Sep 2026SaleJ. E. DavisCEO and PresidentCEO and PresidentSale10,000$2.4M
28 Aug 2026SaleMichael E. PrevoznikSVP & General CounselSVP & General CounselSale22,677$5.5M
28 Jul 2026SaleMark E. DelaneySVP & Chief Commercial OfficerSVP & Chief Commercial OfficerSale1,600$376K
4 Jun 2026SaleKarthik KuppusamySVP, Clinical SolutionsSVP, Clinical SolutionsSale8,147$1.6M
1 Jun 2026SaleJ. E. DavisCEO and PresidentCEO and PresidentSale10,000$1.9M
5 Mar 2026SaleCatherine T. DohertyEVP, Regional BusinessesEVP, Regional BusinessesSale5,558$1.1M
5 Mar 2026SaleMichael E. PrevoznikSVP & General CounselSVP & General CounselSale3,878$800K
5 Mar 2026SalePatrick PlewmanSVP for Diagnostic ServicesSVP for Diagnostic ServicesSale2,855$589K
4 Mar 2026SaleKarthik KuppusamySVP, Clinical SolutionsSVP, Clinical SolutionsSale2,628$538K
3 Mar 2026SaleCatherine T. DohertyEVP, Regional BusinessesEVP, Regional BusinessesSale632$131K

Showing 10 of 22 trades

Source: SEC insider transactions data sets, Quest Diagnostics' Form 4 filings

Trades by members of Congress and officials

Trades members of Congress and senior executive branch officials disclosed, including their families'. Amounts are filed as ranges.

Trades from 20 Oct 2023 to 20 Oct 2026

9 people disclosed 9 purchases and 12 sales of Quest Diagnostics stock since October 2023.

DateMember or officialTypeAmount
4 Sep 2026Rohit Khanna (House, D-CA)House, D-CA · BoughtPurchase$1,001 to $15,000$1K to $15K
23 Jul 2026Donald J Trump (President)President · SoldSale$15,001 to $50,000$15K to $50K
12 Jun 2026Donald J Trump (President)President · SoldSale$1,001 to $15,000$1K to $15K
18 May 2026Donald J Trump (President)President · BoughtPurchase$100,001 to $250,000$100K to $250K
11 May 2026Donald J Trump (President)President · BoughtPurchase$100,001 to $250,000$100K to $250K
30 Mar 2026Alan Armstrong (Senate, R-OK)Senate, R-OK · BoughtPurchase$1,001 to $15,000$1K to $15K
27 Mar 2026Alan Armstrong (Senate, R-OK)Senate, R-OK · BoughtPurchase$1,001 to $15,000$1K to $15K
29 Jan 2026Rohit Khanna (House, D-CA)House, D-CA · BoughtPurchase$1,001 to $15,000$1K to $15K
3 Nov 2025Julie Johnson (House, D-TX)House, D-TX · SoldSale$1,001 to $15,000$1K to $15K
30 Oct 2025Julie Johnson (House, D-TX)House, D-TX · SoldSale$1,001 to $15,000$1K to $15K

Showing 10 of 21 trades

Source: House, Senate and OGE disclosures via the Congress trading monitor

Not on file: no WARN layoff notices under its own name since October 2023.