The hotel heiress was sued by bosses at Hairtech International on Wednesday (11Aug10) for reneging on her contract with the brand by allegedly wearing extensions made by another manufacturer.
But her attorneys insist the $35 million (£23.3 million) suit lacks merit - and they're contemplating filing a countersuit.
A statement from Hilton's spokesperson Dawn Miller reads: ""There is no merit whatsoever to any of these claims. We will pursue all of our defences vigorously and any potential counter claims.""
The blonde socialite was paid $3.5 million (£2.3 million) to endorse Hairtech's Dream Catchers range in 2007.