Buyout firm Thoma Bravo LP has contacted Twitter Inc to express interest in putting together an acquisition offer that would rival Tesla Inc Chief Executive Elon Musk’s $43 billion bid, people familiar with the matter said on Friday.

Thoma Bravo, a private equity firm that had more than $103 billion in assets under management as of the end of December, has informed Twitter that it is exploring the possibility of putting together a bid, the sources said.

It is not clear how much Thoma Bravo would be prepared to offer and there is no certainty that such a rival bid will materialize, the sources cautioned, asking not to be identified because the matter is confidential.

A Thoma Bravo spokesperson declined to comment while Twitter representatives did not immediately respond to a request for comment.

The New York Post reported on Thursday that Thoma Bravo was considering a bid for Twitter.