Labcorp operates the National Genetics Institute, Inc. (NGI), in Los Angeles, California, which develops PCR testing methods.

In 1978, it acquired American Biomedical Corporation, giving it operations in the Southwestern United States and data processing technology.

[6] In the early 1990s, worries about malpractice lawsuits led doctors to conduct more clinical testing before diagnosing, which increased business for the company.

[10] The acquisition price was reduced to $204 million after federal officials issued subpoenas in an investigation of Medicare billing practices.

[9][10][15][16] The company changed its name to Laboratory Corporation of America Holdings and relocated its headquarters to Burlington, North Carolina.

[9] In July 1998, Labcorp acquired the Michigan-based laboratory division of Universal Standard Healthcare (UHCI) and made an equity investment in the company.

[26][27] In January 2003, Labcorp acquired Dianon, a provider of oncology and genomic diagnostic testing services, for $598 million in cash.

[20][31] In March 2005, Labcorp acquired Esoterix, a provider of specialty reference testing, for approximately $150 million in cash from Behrman Capital.

[33] In January 2008, Labcorp acquired Tandem Labs, a contract research organization specializing in advanced mass spectrometry, immunoanalytical support, pharmacokinetics, and pharmacodynamics.

[34][33] In June 2009, Labcorp acquired Monogram Biosciences, a diagnostic lab specializing in HIV resistance testing, for approximately $155 million including debt.

[41][42] In May 2012, Labcorp Clinical Trials sold its European biological sampling kit building operation located in Hamburg to Marken.

[44] In September 2013, Labcorp acquired MuirLab, the clinical laboratory outreach business of John Muir Health.

[45] In November 2014, Labcorp acquired LipoScience, a developer of diagnostic tests based on nuclear magnetic resonance spectroscopy measuring heart disease risk, for $85 million.

[77] In 1992, the company was one of the first to be prosecuted as part of Operation Labscam, a nationwide crackdown on fraud in the healthcare system initiated by the U.S. Attorney's Office in San Diego, California.

The company and others were accused of routinely submitting false claims to Medicare and Medicaid for unnecessary tests on blood samples that physicians had never ordered.

[81] In 2012, Labcorp was criticized for its practice of paying the salaries of genetic counselors in hospitals and doctors' offices, which is perceived to be a possible conflict of interest.

The most notable case was the 2005 false accusation of Washington hairdresser Andre Chreky, who spent $200,000 and years in court proving, despite a false-positive test, that he was not the father.

[86] In 2024, Labcorp faced a class action lawsuit for allowing Google to collect confidential patient information such as appointments made and website login details.