Quest Diagnostics Incorporated (DGX)

Quest Diagnostics' stock price increased by 16.45% between July 15, 2024, and July 14, 2025, and has rallied 38% over the past year, outperforming the industry and the S&P 500. Key events impacting the stock include strong Q1 2025 financial results with 12.1% revenue growth, contributions from acquisitions and partnerships, growth in the Advanced Diagnostics portfolio, focus on operational excellence and technology adoption, a dividend increase, plans to develop a Multi-cancer Stratification Blood Test, and an increase in short interest indicating decreased investor sentiment.

The clinical testing industry, including Quest Diagnostics, is subject to seasonal fluctuations, with testing volumes declining during vacation and major holiday periods. Factors such as severe weather or public health emergencies can also deter patients from seeking tests. In the first quarter of 2025, weather impacts reduced volume growth, though demand rebounded in March.

Quest Diagnostics, Inc. (DGX) is a leading American clinical laboratory and a Fortune 500 company in the healthcare sector, specifically the medical diagnostics and screening industry, established in 1967. It provides diagnostic testing, information, and services to patients, clinicians, hospitals, and employers, with over 95% of its revenue from clinical testing, anatomic pathology, esoteric testing, and substance abuse testing. Quest Diagnostics offers more than 45,000 different types of diagnostic tests, serving approximately one in three adult Americans annually, including routine blood tests, genetic testing, molecular genomics and oncology tests, infectious disease testing, neurological disorders testing, women's health, employment and court-ordered drug testing, clinical trials testing, risk assessment services, and healthcare information technology solutions.

Quest Diagnostics operates extensively in the United States with a national network of laboratories and patient service centers. It also has an international presence in Puerto Rico, Mexico, and Brazil, with operations in India and Ireland. Its products and services are used by customers on six continents, and it collaborates with hospitals and clinics globally, performing specialized testing for hospitals and laboratories in over 50 countries.

Quest Diagnostics has maintained a strong brand reputation, being named one of FORTUNE's "World's Most Admired Companies" for the tenth consecutive year in 2024. However, it was linked to inaccuracies in cervical smear tests in 2018, leading to lawsuits and a government inquiry. More recently, in July 2025, the company released its 2024 Corporate Responsibility Report.

Quest Diagnostics has a widely held ownership structure, with institutional investors holding 87.4% of shares as of Q4 2023. Major institutional owners include Vanguard Group Inc, BlackRock Inc, and State Street Corporation. As of July 2025, institutional investors hold 88.06% of the stock, while insiders hold only 8.16%, and insiders have sold more company stock than they have bought in the past three months.