Institutional Shareholder Services (ISS) and Glass Lewis have advised Twitter shareholders to support Elon Musk’s proposed takeover bid, as the billionaire continues his efforts to terminate the deal.

The Tesla CEO has been attempting to back out of his bid to buy Twitter for $44-billion for over a month, arguing Twitter lied about the number of fake accounts on the platform. Twitter has since taken Musk to court, seeking enforcement of the merger deal.

Musk’s most recent effort to exit the bid saw the billionaire seize on a whistleblower report by Twitter’s former security chief, arguing that such allegations raised in the report would breach several aspects of the merger agreement struck in April.

“The Zatko complaint alleges far-reaching misconduct at Twitter-all of which was disclosed to Twitter’s directors and senior executives, including [CEO] Parag Agrawal -that is likely to have severe consequences for Twitter’s business,” an August 29 regulatory filing stressed.

According to Bloomberg, ISS and Glass Lewis have issued reports urging Twitter shareholders to vote for the merger.

ISS described the situation as “unique” and said investors should “focus on the details of the proposal itself instead of the noise around it.”

The proxy advisory firm said while the lack of an auction for the company would generally be a cause for concern, no other rival bids have emerged.

Glass Lewis said the offer price would give shareholders “a relatively attractive exit price, and a premium for the company’s unaffiliated shareholders.”

Shares in Twitter closed at $39.32 on August 30, a 1.8% drop on opening.