A business reporter.
Musk denied having an affair with the wife of Brin.
The Wall Street Journal reported that Mr Musk and Mr Brin had ended their friendship over the affair.
The report was referred to by Mr Musk as "total bs".
Mr Musk said that he and Mr Brin were at a party together.
According to the Wall Street Journal, Mr Musk was involved in a brief affair late last year with another woman.
The friendship between the two high-profile technology billionaires ended after Mr Brin filed for divorce.
Mr Musk has only seen Nicole twice in three years. It's nothing romantic.
This is total bs. Sergey and I are friends and were at a party together last night!
I’ve only seen Nicole twice in three years, both times with many other people around. Nothing romantic.