Though the timing is unclear, multiple outlets took note Thursday that Heard's Twitter account, @realamberheard, is deactivated. A screen on the page now reads "This account doesn't exist."
Heard, 36, still has an Instagram account with 5.3 million followers, where her most recent post is her June 1 statement after the verdict in her Virginia defamation trial with ex-husband Johnny Depp.
A rep for Heard did not respond to PEOPLE's request for comment.
Musk, who previously dated Heard after her split from Depp, recently bought Twitter and became its CEO. Shortly before the takeover was finalized, the billionaire issued a public letter to advertisers, assuring them he didn't want the platform to "become a free-for-all hellscape, where anything can be said with no consequences!"
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A rep for Musk, 51, previously said he and Heard, who'd broken up by August 2017, "didn't start seeing each other until May 2016, and even then it was infrequent. Their relationship didn't become romantic until some time later."
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Over a year after the breakup, Heard told The Hollywood Reporter in December 2018, "Elon and I had a beautiful relationship, and we have a beautiful friendship now, one that was based on our core values. Intellectual curiosity, ideas and conversation, a shared love for science. We just bonded on a lot of things that speak to who I am on the inside. I have so much respect for him."
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During the Virginia trial earlier this year, Christian Carino, a talent agent who at one point represented both Heard and Depp, shared text messages he exchanged with Heard about her relationship with Musk. When discussing Heard's breakup with Musk back in August 2017, Carino recalled questioning why she was "sad" if she wasn't "in love with him to begin with." A lawyer for Depp read a text exchange between Carino and Heard in which she admitted she was "just filling space" with Musk after her Depp split.
Heard texted Carino: "I hate that yet again a man let's me fall on the spikes by myself. ... Meaning, they are mad at me for leaving them and put things like this out there." Carino then replied, "You could avoid all this if you stopped dating über-famous people. You can be with a big man who isn't famous."
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The verdict in the trial was handed down on June 1, with a seven-person jury siding mostly with Depp, 59, finding that Heard defamed him in her 2018 op-ed about domestic abuse, though she didn't mention him by name in the article. He was awarded more than $10 million in damages, while Heard won one of her three defamation counterclaims and was awarded $2 million in damages. They are now both appealing the verdicts.