Shares in Mayne Pharma Group Ltd (ASX: MYX) have jumped more than 10% after a court denied a bid by the company's takeover suitor, Cosette Pharmaceuticals Inc, to back out of the deal.
But shareholders in the company could make another 16% on top of that in easy fashion if the takeover goes ahead at the $7.40 offer price, which is expected to happen next month. More on that below.
Extended legal stoush
Mayne Pharma has been tied up in a legal fight with Cosette since May this year, after the US company said it would rescind its takeover offer for the company.
Cosette was arguing that there were a number of factors that constituted a "material adverse change" with regards to Mayne's business, including a trading update in April and certain correspondence with the US Food & Drug Administration (FDA).
Mayne, at the time, denied that the arguments put forward by Cosette constituted a material adverse change as defined in the scheme implementation deed for the deal and said that the company would challenge Cosette's right to back out.
As Mayne Pharma said in a statement to the ASX in May:
Mayne Pharma maintains its position that all information relevant to the financial position of Mayne Pharma has been disclosed to the market in the earnings announcement released on 22 April and that there is now new information required to be disclosed in light of the contents of the Cosette notice.
The Cosette deal, announced to the market in February, offered Mayne shareholders $7.40 per share cash, which at the time was a 37% premium to the prevailing share price.
Despite Cosette's ongoing attempt to back out of the deal, Mayne went ahead with a shareholder vote in June, where the resolution to go ahead with the deal was passed soundly, with 99.06% of shares voted in favour.
Meanwhile, Mayne lodged proceedings in the New South Wales Supreme Court, which this week ruled in favour of Mayne.
As the company said in a statement to the ASX on Thursday:
Mayne Pharma is pleased to announce that in a judgment delivered on 15 October 2025, the Supreme Court of New South Wales found in favour of Mayne Pharma and dismissed Cosette's claims. Mayne Pharma will now take all steps within its power to implement the scheme.
Still value in Mayne shares
The deal still requires approval from the Foreign Investment Review Board, and it also needs to be approved by the Supreme Court at a hearing scheduled for 22 October.
Mayne said, subject to these conditions being met, it was anticipated that the scheme would become effective on 23 October.
Mayne shares jumped sharply on the news, up 12.2% to $6.35; however, they are still well shy of the $7.40 takeover price.
Should shareholders receive that in cash, they'll bank another 16.9% in gains based on Thursday's price mid-morning.
