Elon Musk announced on Friday that his plan to buy Twitter in a proposed $44 billion deal is " temporarily on hold " as he tries to pinpoint the exact number of spam and fake accounts it has.

Here's a look at some of what's transpired between the billionaire Tesla CEO and the social media platform.

1. March 26: Musk, who has 80 million Twitter followers and is active on the site, said that he is giving "serious thought" to building an alternative to Twitter, questioning free speech on the platform andwhether Twitter is undermining democracy.

2. April 4: A regulatory filing reveals that Musk has rapidly become the largest shareholder of Twitter after acquiring a 9% stake, or 73.5 million shares, worth about $3 billion.

3. April 5: Musk is offered a seat on Twitter's board. CEO Parag Agrawal said in a tweetthat "it became clear to us that he would bring great value to our Board."

4. April 11: Twitter CEO Parag Agrawal announces Musk will not be joining the board after all.

5. April 14: Twitter reveals in a securities filing that Musk hasoffered to buythe company outright for about $44 billion.

6. April 15: Twitter's board unanimously adopts a "poison pill"defense in response to Musk's proposed offer, attempting to thwart a hostile takeover.

7. April 21: Musk lines up $46.5 billion in financing to buy Twitter. Twitter board is under pressure to negotiate.

8. April 25: Musk reaches adeal to buy Twitter for $44 billion and take the company private. The outspoken billionaire has said he wanted to own and privatize Twitter because he thinks it's not living up to its potential as a platform for free speech.

9. April 29: Musk sellsroughly $8.5 billion worth of shares in Tesla to help fund the purchase of Twitter, according to regulatory filings.

10. May 5: Musk strengthens his offer to buy Twitter with commitments of more than $7 billion from a diverse group of investors including Silicon Valley heavy hitters like Oracle co-founder Larry Ellison.

11. May 10: In a hint at how he would change Twitter, Musk says he'd reverse Twitter's ban of former President Donald Trump following the Jan. 6, 2021 insurrection at the U.S. Capitol, calling the ban "morally bad decision" and "foolish in the extreme."

12. Friday, May 13: Musk said that his plan to buy Twitter is "temporarily on hold." Musk said that he needs to pinpoint the number of spam and fake accounts on the social media platform. Shares of Twitter tumble, while shares of Tesla rebound sharply.