Bill Gates formally stepped down from Microsoft's board of directors last year after his fellow board members agreed that he should. He made a move after the board looked into an alleged sexual relationship between the billionaire and a female Microsoft employee.

Wall Street Journal said a law firm hired by the board of directors began an investigation in 2019. A Microsoft engineer claimed in a letter that she had a sexual relationship with Gates for years. People familiar with the situation provided the details to the Journal.

During the process, many board members reportedly concluded that Gates could not stay on the board of the organization he co-founded and even led for decades. But Gates had formally resigned before the board completed the inquiry into the matter.

While Microsoft initially did not respond to a request for comment, they did confirm that they were looking into the matter. 

NPR cited a Microsoft spokesperson's claim the organization got a tip during late 2019 that Gates planned to start an intimate relationship with a company employee in 2000.

Hence, Microsoft allegedly issued an extensive report to the specific employee who had raised the issue during the investigation.

According to  CNet, Gates could not be reached for comment. Still, a spokesman for the Microsoft co-founder acknowledged the existence of a particular affair that occurred nearly 20 years ago and supposedly ended amicably. 

She stated that the decision to leave the board had little to do with the situation. In reality, Gates said that he only wanted to devote more time to his philanthropy, which he officially began a few years ago.

Gates allegedly agreed to resign from the official Microsoft board of directors on March 13, 2020, to "dedicate more time" to his philanthropic pursuits. These interests including education, global health, growth, and his growing involvement in combating climate change. Gates and his wife officially revealed earlier this month that they would be ending their 27-year marriage at some point.

Another Wall Street Journal report said that Gates spent time with Jeffrey Epstein. Epstein is a convicted sex trafficker partly responsible for Melinda Gates' decision to seek a divorce. According to reports, Melinda was concerned about Epstein's friendship with Bill. He has met with Epstein "many times" since 2011, according to a 2019  New York Times report. Bill Gates denies being acquainted with Epstein as well as having a business relationship with him.

Bill and Melinda Gates Bill and Melinda Gates pose in front of the Elysee Palace after receiving the award of Commander of the Legion of Honor by French President Francois Hollande on April 21, 2017 in Paris, France. Frederic Stevens/Getty Images