The petition for both a name change and a new birth certificate reflecting her new gender identity was filed with the Los Angeles County Superior Court in Santa Monica in April. It came to light recently in some online media reports.
The former Xavier Alexander Musk, who recently turned 18, the age of consent in California, has asked the court to change her gender recognition from male to female and to register her new name, according to court documents available online through PlainSite.org.
Her new name was redacted in the online document. Her mother is Justine Wilson, who divorced Musk in 2008.
There was no further explanation of the rift between Musk's daughter and her father, the Tesla and SpaceX chief who is attempting a $44 billion takeover of social media platform Twitter.
Neither a lawyer who represents Musk nor the Tesla media office immediately responded to Reuters emails requesting comment on Monday.
In May, about a month after the name and gender change document was filed, Musk declared his support for the Republican Party, whose elected representatives support a raft of legislation that would limit transgender rights in states across the country.
Musk has weighed in on the issue of transgender people choosing their preferred pronouns, tweeting in 2020, "I absolutely support trans, but all these pronouns are an esthetic nightmare."
(Reporting by Daniel Trotta: Editing by Ross Colvin and Gerry Doyle)