The Tesla founder allegedly had a fling with Brin's wife Nicole Shanahan, allegedly leading to their divorce.
The WSJ report, citing sources familiar to those involved, claims that Musk and Shanahan had a "brief affair," which subsequently led Brin to file for divorce earlier this year, and ended a long-standing friendship between Brin and Musk.
On Sunday evening, Musk took to Twitter to deny the report, saying, "Yeah, the character assassination attacks have reached a new level this year, but the articles are all nothing-burgers." The Tesla CEO went on to say, "I work crazy hours, so there just isn’t much time for shenanigans. None of the key people involved in these alleged wrongdoings were even interviewed!"
Musk continued, galvanizing his supporters to call out the publication for its reporting, tweeting, "Call them out on it, I guess. WSJ is supposed to have a high standard for journalism and, right now, they are way sub tabloid. WSJ should be running stories that actually matter to their readers and have solid factual basis, not third-party random hearsay."
On Monday, Musk took to Twitter once more, this time posting what's seemingly photo evidence of his friendship with Brin.
The WSJ reported that Brin filed for divorce in January citing "irreconcilable differences," and stated that the pair had been separated since Dec. 15. According to the report, Musk and Shanahan's alleged fling occurred in early December, at the Art Basel event in Miami -- which ran from Dec. 2 to Dec. 4.
Musk and Brin have long been friends, and have often spoken of their friendship in interviews. Brin was reportedly among the first people to be given a Tesla vehicle when production got off the ground, and Brin reportedly gave Musk $500,000 in 2008 to keep Tesla afloat during the financial crisis.
Since the alleged affair, Brin has reportedly sought to extricate himself from any involvement in Tesla or with Musk's companies, and tensions between the billionaires have been mounting.
The alleged affair came several months after Musk had broken up with his on-and-off girlfriend, singer Grimes, with whom he shares two children. Musk is the father of 10 children in total -- including one who recently changed their name and publicly disavowed Musk.
Brin and Shanahan share a 3-year-old daughter. Meanwhile, Brin shares two children with ex-wife Anne Wojcicki, the tech entrepreneur behind 23andMe.
According to the WSJ report, Musk allegedly dropped to one knee at a party and openly begged for Brin's forgiveness. The Google co-founder reportedly acknowledged the apology, but they have not rebuilt their relationship.
Meanwhile, Brin and Shanahan are reportedly in divorce mediation and both sides are contesting the settlement amount.
Musk, meanwhile, has been at the center of a string of controversies and feuds in recent months, including his tumultuous attempt to purchase Twitter, and subsequent legal battle after attempting to back out of the deal.
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