Twitter Inc. implemented a 'poison pill' on Friday to restrict Elon Musk's ability to increase his stake in the social media site. A buyout group emerged to oppose his $43 billion takeover attempt.

According to persons familiar with the subject, Thoma Bravo, a technology-focused private equity firm with more than $103 billion in assets under management as of the end of December, has told Twitter that it is studying the prospect of putting together a proposal.

It is unclear how much Thoma Bravo would be willing to offer. There is no guarantee that such a rival bid will materialize, the sources added, declining to be identified due to the nature of the case.

A spokesperson for Thoma Bravo declined to comment, and Twitter staff did not reply immediately to a request for comment. According to the New York Post, Thoma Bravo was exploring a bid for Twitter.

Twitter announced on Friday that it had implemented a poison pill that would dilute anyone acquiring a stake in the firm more significant than 15% by selling additional shares at a discount to existing shareholders. The poison pill, properly known as a shareholder rights plan, will be in effect for 364 days.

This does not exclude Musk from presenting his offer directly to Twitter shareholders via a tender offer. While the poison pill would prevent the majority of Twitter shareholders from selling their shares, the tender offer would enable them to express their support or opposition to Musk's proposal.

"It is a predictable defensive measure for the board to go down that will not be viewed positively by shareholders given the potential dilution and acquisition unfriendly move," Wedbush analyst Dan Ives tweeted on Friday.

Thoma Bravo's interest in Twitter raises the prospect of other private equity groups bidding for the company. According to data source Preqin, the global personal equity business has over $1.8 trillion in dry powder. Unlike large technology conglomerates, most private equity firms would not be subject to antitrust rules if they acquired Twitter.

It is still conceivable for a private equity firm to bolster Musk's candidacy by collaborating with him rather than competing with him. Musk's criticism of Twitter's reliance on advertising for the majority of its revenue, on the other hand, has made some private equity firms wary of partnering with him, according to industry sources. A healthy cash flow makes it much easier to finance a leveraged buyout.

Silver Lake, a private equity fund with more than $90 billion in assets under management, would be an ideal partner for Musk, given it financed his failed $72 billion bid for Tesla Inc four years ago. Egon Durban, co-chief executive of Silver Lake, is also a member of Twitter's board of directors.

However, Durban did not recuse himself on Thursday when Twitter's board of directors met for the first time to discuss Musk's offer, according to sources familiar with the subject, indicating that Silver Lake has not sought to partner with Musk or make its bid thus far.

Silver Lake may choose to enter the transaction as a buyer. On Friday, a spokeswoman for Silver Lake did not immediately respond to a request for comment.

'FINAL AND BEST OFFER'

Twitter's balance sheet has more than $6 billion in cash, and its annual cash flow is close to $700 million, providing some reassurance to banks assessing whether to issue finance for a deal. Nonetheless, a leveraged buyout of Twitter might be the largest in history, requiring the collaboration of many buyout companies and other critical institutional investors.

According to Forbes, Musk is the world's wealthiest individual, with a net worth of $265 billion. He has, however, established a ceiling on the amount he is willing to spend. He informed Twitter on Wednesday that his all-cash proposal of $54.20 per share was his "best and final offer" and that if it were rejected, he would reevaluate his status as a Twitter shareholder. Musk owns more than 9% of Twitter, making him the company's second-largest stakeholder after mutual fund behemoth Vanguard.

Musk tweeted on Thursday that Twitter shareholders should vote on his offer and included a poll in which most users agreed. Twitter's board of directors is still evaluating Musk's offer and will only submit it to a vote of its shareholders if it approves. Twitter shares dipped on Thursday, signaling that most investors believe the company's board will reject Musk's bid as insufficient and lacking in details about finance.

According to sources familiar with the subject, Twitter's board of directors is anticipated to take several additional days to evaluate Musk's bid and craft a response. A weekend outcome is improbable, the sources indicated.

Goldman Sachs Group Inc has advised Twitter's board of directors during their discussions. According to Bloomberg News, the board has appointed JPMorgan Chase Co Inc as a second financial adviser.