The front-runner to buy LifeLabs Medical Laboratory Services, Canada’s largest diagnostics platform, from the pension plan owner is one of the biggest medical testing corporations in America. After the auction, Quest Diagnostics Inc., DGX-N, of New Jersey, is nearing the end of talks to purchase LifeLabs from the Ontario Municipal Employees’ Retirement System (OMERS).

According to the sources, Quest purchased Toronto-based Andlauer Healthcare Group Inc. AND-T was outbid by $100 million to acquire the business for over $1.3 billion. If Quest succeeds, it will be in part because of its deep understanding of LifeLabs’ operations. When CML Healthcare Inc., the forerunner to LifeLabs, was up for sale in 2013, OMERS outbid the American corporation.

LifeLabs, a Toronto-based company, employs 5,700 people and conducts 112 million tests a year at locations across Ontario, British Columbia and Saskatchewan. The company operates 16 laboratories and 382 collecting centers.

Over the previous 20 years, Quest has grown through a number of acquisitions in the US, Europe, and South America. Across 2,000 locations, its 47,000 employees test one in three Americans annually. The corporation is valued at $15.4 billion on the market and is listed on the New York Stock Exchange.

One of the biggest U.S. medical testing corporations, Laboratory Corp. of America Holdings, or Labcorp, is the owner of LifeLabs’ primary domestic competitor, Dynacare. With 200 collection stations and laboratories spread across four provinces—Alberta, Manitoba, Ontario and Quebec—Dynacare employs 2,400 people. For $480 million, North Carolina-based Labcorp purchased Dynacare in 2002.

For the benefit of firefighters, police officers and other government workers, OMERS is in charge of $129 billion in assets. The pension fund’s $36 billion infrastructure portfolio includes LifeLabs.