the patent holder holds the responsibility for defending the patent if infringement is hurting the licensee's revenue. or so it has been for every tech licensure deal i've had anything to do with
and if they fail to do so they can be sued by the licensee
and a licensee who stands to make megabucks on a license is a fucking idiot if they say "well tough shit guy, go lose that lawsuit and let our competition eat our lunch on this product because we can't be arsed to pony up a little more money to help you out"
