Twitter's board readies against hostile takeover

Twitter's board has armed itself against a possible hostile takeover - a day after billionaire Elon Musk made a $43bn (£33bn) offer to buy the platform.

It has adopted what is known as a "limited-duration shareholder rights plan," also known as a "poison pill".

The move will prevent anyone from having more than a 15% stake in the company.

It does this by allowing others to buy additional shares at a discount.

The Twitter board detailed its defence plan to the US Securities and Exchange Commission and put out a statement saying it was needed because of Mr Musk's "unsolicited, non-binding proposal to acquire Twitter".

Josh White, former financial economist for the Securities and Exchange Commission told the BBC that a poison pill is "one of those last lines of defence against a hostile bid takeover".

"We call it the nuclear option," he said.

Because Mr Musk had signalled that he was not willing to negotiate a higher price, the Twitter board went ahead with the poison pill.

Mr White says he was surprised by Mr Musk's negotiation tactic, because if the end game is to acquire the company, it might not be the "right approach".

The plan will expire on 14 April next year.

Chief Executive Parag Agrawal previously said the company was not being "held hostage" by the offer.

Mr Musk announced a 9.2% stake in the company earlier this month, but he is not the largest shareholder anymore. Asset management firm Vanguard Group disclosed that its funds now own a 10.3% stake.

Mr Musk has said he believes Twitter is limiting freedom of speech on the platform and he reiterated this at the Vancouver event. He has said his primary motivation would be to expand free speech on Twitter.

Mr Musk is being advised by the US investment bank Morgan Stanley. Meanwhile Twitter is receiving help from two banks, Goldman Sachs and JP Morgan, according to Bloomberg.