By Dan Levine SAN FRANCISCO (Reuters) – A U.S. judge on Monday ruled that patent owner Intellectual Ventures can go to trial next month against one of its investors even though IV will not be allowed to present key damages evidence to a jury, according to a court filing. Chipmaker Xilinx invested in two Intellectual Ventures funds and licensed a portion of IV’s patents, but resisted IV’s entreaties to license more patents in 2010, court filings show. Xilinx Inc eventually asked a California federal judge to declare those IV patents invalid, while IV countersued in Delaware, accusing Xilinx of infringement. The proceeding comes in the midst of a heated debate over whether it is too easy for patent owners to extract large royalty payments, and whether patent buying firms spur or stifle innovation.