Twitter’s board has unanimously approved a limited-term shareholder rights plan. This follows Tesla CEO Elon Musk’s $54.20 per Share offer to make the social media giant private.

The plan is also known as a “poison pills” and shareholders’ rights will be exercisable if any entity, person, or group acquires beneficial control of 15% or more Twitter’s outstanding common shares in a transaction that has not been approved by the board. If the rights are granted, shareholders will have the right to purchase additional common stock at a discount rate.

According to the board, the plan is designed to allow all shareholders to realize the full potential of their investment in Twitter. It will also “reduce the possibility that any entity or person gains control of Twitter through open-market accumulation without paying all shareholders a suitable control premium or giving the Board sufficient time for informed decisions and to take actions that are in shareholders’ best interests.”

This plan is intended to allow all shareholders to realize the full benefit of their investment in Twitter. It will also “reduce the possibility that any entity or person gains control of Twitter through open-market accumulation without paying all shareholders a suitable control premium or giving the Board sufficient time for informed decisions and to take actions that are in shareholders’ best interests.”

This plan will expire on April 14th 2023. However, it does not stop Twitter’s board engaging with parties and accepting an acquisition offer if they feel it is in the company’s best interests.

Musk’s bid for $43 billion comes less than two months after he announced a 9.2% stake at Twitter on April 4. Musk was initially invited by Twitter to join its board. However, he declined. Musk wouldn’t have been allowed to own more that 14.9% of Twitter stock during his time on the board. He would also be unable for the 90-day period following his departure. Musk’s term on the board would have ended at Twitter’s annual meeting in 2024.

Although Elon Musk stated that the offer was his “best and last”, he said at TED2022 that he has a plan B. He declined to give more details when asked.