This case comes to us on an interlocutory appeal from the United States District Court for the Northern District of California. The certified question concerns the limits on standing to bring so-called Walker Process antitrust claims. The Supreme Court in Walker Process Equipment, Inc. v. Food Machinery & Chemical Corp., 382 U.S. 172 (1965), held that antitrust liability may attach when a party uses a patent to obtain or preserve a monopoly if the patent was procured through intentional fraud on the Patent and Trademark Office (“PTO”). The question in this case is whether an antitrust action against the owner of a patent, based on the Walker Process theory of liability, can be brought by a direct purchaser of goods that are protected by the patent, even if the purchaser faces no threat of an action for patent infringement and has no other basis to seek a declaratory judgment holding the patent invalid or unenforceable. We hold that the district court was correct to rule that a direct purchaser is not categorically precluded from bringing a Walker Process antitrust claim, even if it would not be entitled to seek declaratory relief against the patentee under the patent laws.