Final submissions were made to the Court on October 9 but the judge, Ms Justice Mary Finlay Geoghegan, has gone away to write her judgement rather than giving it orally at the end of the submissions. When reserving judgement the judge said that the case involved difficult questions which needed to be resolved.
Karen Millen alleges that Dunnes copied certain items from its ranges in 2005 such as a Karen Millen "faux shrug cami top" and a striped shirt. It said that Dunnes put similar items on sale in its own stores in 2006. Dunnes denied the allegations and said the "faux shrug cami top" had been around before and that the shirt was just like any other shirt. However Mosaic Fashions claimed to have evidence that Karen Millen was specifically mentioned by Dunnes when it instructed a designer.
This is one of three cases being brought against Dunnes by Mosaic. However the judge will rule on the Karen Millen action before hearing similar cases brought by Mosaic's Coast and Whistles brands.
The judge may refer certain issues of the case to the European Court of Justice, which would be unlikely to give its judgment until 2009, according to legal sources. The case would then return to the Dublin High Court.
However Geoghegan may still opt to read her own judgement in December.
Whichever path the case follows, this will be the first reported judgement involving fashion in the British Isles under the 2001 European Union's Community Unregistered Design Right regulation.
Stephen Sidkin, partner at law firm Fox Williams, said fashion companies in similar situations were likely to look to the judgement and seek to draw similarities or differences between the facts in this case and their own.
He added: "What the Karen Millen case and other recent disputes show is that design rights and copyrights in the fashion world can be asserted when there is a commercial rationale for doing so. Is this the start of a trend? Or are these cases a corrective to the abuses of the retail outlets. Who will now settle and stop seeking to 'get away with it'? In either view, it would be sensible for derivative retail outlets and 'over-inspired' designers to assess the risk of litigation, obtain legal advice if necessary, and put in place insurance policies to cover the legal fees."