ANZ yesterday prevailed over its opponents in a preliminary Federal Court ruling on the legal issues at stake in a test case over alleged overcharging of penalty fees.The bank is defending a class action being brought against it by 34,000 claimants who seek the refund of an estimated A$50 million in fees. The claimants say the fees are void or unenforceable.Litigation funder IMF (Australia) is funding the case, with law firm Maurice Blackburn managing the action.Yesterday's ruling dealt mainly with whether the fees levied by ANZ - $35 in most cases - were the result of a breach by the customers of their contracts with the bank.Justice Michelle Gordon analysed 17 different fees across four ANZ product categories, using examples from the accounts of three customers selected by Maurice Blackburn.Gordon ruled that 13 of the 17 fees "are not capable of being characterised as a penalty". The fee types in this group include those labelled by the bank as honour fees, dishonour fees, overlimit fees and non-payment fees.She ruled that four late payment fees on consumer credit cards and commercial cards "are capable of being characterised as a penalty".Having found in some cases that the fees applied were the result of a breach does not make the fees a "penalty" in a narrow legal sense, she said. This will be the subject of a further hearing some time in 2012, which will look into the costs incurred by ANZ.Gordon's ruling does not preclude the claimants from persisting with their claims for damages in respect of the other fee types. Rather, it means they cannot rely on the law of penalties to support their case and must turn to other lines of argument, using other legislation such as that relating to unconscionable conduct.However, the claimants hope to resurrect their original arguments.IMF (Australia) said in a media release that it "will consider an appeal directly to the High Court".Andrew Watson, a partner at Maurice Blackburn, said the claimants were likely to appeal Gordon's ruling.ANZ is also considering an appeal over those aspects of the judge's ruling that adversely affect its case.Further skirmishing over which law to apply means a trial on the substantive issues may not take place until late next year.