The case is one of the largest claims against a British law firm or merchant bank and is the largest taken out against either Warburg or Linklaters.
The trial is due to start on 11 January in the High Court, which has set aside 20 weeks for the hearing.
Yeoman is claiming that Warburg and Linklaters were negligent in their advice to the Irish group when it paid pounds 93m for a rival leasing group, CLF, five years ago.
Only four months after the purchase, the discovery of a pounds 12m loss at one of CLF's subsidiaries, Technology for Business, forced the group into an emergency pounds 15m rights issue, which was underwritten by Warburg.
Despite the rights issue, further problems emerged within Yeoman, and the group was forced into a refinancing in 1991 that led to its shares being delisted by the London Stock Exchange.
The action brought by Yeoman is actually a counter-claim against a writ taken by Linklaters claiming pounds 230,000 of unpaid fees from Yeoman over the deal.
In its counter-claim, Yeoman is alleging that Warburg and Linklaters should have identified the problems within CLF. It says that the true value of CLF at the time it bought the company was just pounds 25m and is suing for the pounds 68m difference plus accumulated interest.
Both Warburg and Linklaters are vigorously defending the action. Warburg, following advice from the law firm Berwin Leighton, has not disclosed the action in its accounts as a contingent liability, despite the fact that the banks that have lent more than pounds 40m to Yeoman have set aside a special fund to pay for the legal action because of their confidence of its success.
Linklaters is denying liability. It has asked another firm, Barlow Lyde-Gilbert, to advise it on its defence, and is arguing that there was contributory negligence on the part of Yeoman.
No one on either side will deny that it will be a long and unpleasant battle.