PHILADELPHIA, Nov. 12 -- Nichia Corp. has filed a Sherman Act antitrust claim against Rohm Co. Ltd. and Cree Inc. in the US District Court for the Eastern District of Pennsylvania. The claim asserts that Rohm and Cree entered into a conspiracy to exclude Nichia from the US market and that Rohm knowingly asserted fraudulently obtained and invalid US patents against Nichia to further that conspiracy. Nichia's antitrust claim points to events leading up to and culminating in several agreements between Rohm and Cree. In particular, the antitrust claim asserts that Rohm fabricated a domestic industry to obtain ITC jurisdiction by entering a license agreement with Cree in December 2000, three days before Rohm filed its ITC complaint against Nichia. The antitrust claim allows Nichia to pursue discovery that Nichia believes Rohm attempted to avoid with its abrupt ITC complaint withdrawal in April 2001. Rohm withdrew its ITC complaint seven days after the ITC judge ordered discovery on antitrust issues and shortly before Rohm was required to submit related documents. The US District Court action also allows Nichia to pursue monetary damages and injunctive relief against Rohm and Cree.