Lion Nathan has lost a key court case, tabled as part of its takeover bid for Coopers Brewery.

The Trans-Tasman beer and wine group saw the Australian Federal Court dismiss an appeal to reverse a buyback run by Coopers in 2003 for A$45.01 (US$33.95) a share.

Lion claimed that the buyback had by-passed the pre-emptive rights agreement it holds with Coopers but the court refused to accept that the move was unlawful.

Coopers is due to hold an EGM tomorrow (14 December) to vote on removing the pre-emptive rights deal, which allows Lion to buy shares in the family-held brewer if they have not been purchased by either existing shareholders or Coopers' superannuation fund manager, AMP.

If Coopers shareholders vote in favour of the removal, then Lion's takeover bid would be effectively over.

Lion maintains, however, that it has four other legal challenges on the go, which could keep it's A$310-per-share offer afloat.