Eighteen months later, that happy person apparently was him, as they tied the knot again in July 2013.
But the rekindled romance didn't last. On Wednesday – the day many people make vows for the coming year – the couple officially broke their marital vow. Musk filed for divorce in Los Angeles County Superior Court on New Year's Eve.
The couple said they were splitting amicably and that Musk agreed to give Riley $16 million in cash and other assets as part of a financial settlement, according to a joint statement. A divorce filing said property would be split based on a prenuptial agreement.
Musk made a fortune co-founding PayPal and has gone on to start SpaceX and Tesla Motors. Riley appeared in Pride & Prejudice, Inception and St. Trinians.
The couple first wed in 2010. They didn't have any children, but Musk has five sons from a previous marriage.
Musk and Riley were together for a year after they remarried, but they have lived apart the past five months while Riley wrote and directed her first feature film, Scottish Mussel, in the United Kingdom.
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