Twitter is adopting a poison pill strategy that poses a roadblock to Elon Musk’s offer to buy all of the company’s shares and take the company private.

The social media platform’s board of directors approved a limited-duration shareholder rights plan, which will enable shareholders to “realize the full value of their investment in Twitter” and “reduce the likelihood that any entity, person, or group gains control of Twitter through open market accumulation,” according to a press release Friday.