Federal Circuit Court of Appeals Clarifies Experimental Use Exception

A split U.S. Court of Appeals for the Federal Circuit has upheld a decision invalidating a patent because the patented invention was in public use more than a year before the patent was filed. New Railhead Mfg., L.C.C. v. Vermeer Mfg. Co., Case No. 02-1028 (July 30, 2002).

New Railhead involved two patents. The `283 patent describes a drill bit used for horizontal directional drilling of rock formations; the `743 patent describes a method for such horizontal directional drilling. The district court granted a motion for summary judgment invalidating the `743 patent because of prior public use. The evidence presented established that the inventor allowed an acquaintance to test the durability of drill bits that were the physical embodiment of the `283 patent at a public job site, and that the acquaintance repeatedly used the method described in the `743 patent to help perform those tests.

The Federal Circuit affirmed. The court rejected the plaintiff’s argument that the public testing of the drill bits constituted an experimental use that should not invalidate the `743 patent. The court found that it was of "crowning importance" that the inventor’s acquaintance was testing the drill bit claimed in the `283 patent but not the method described in the `743 patent. Deposition testimony indicated that the method described in the `743 patent had already been successfully tested. As the method of the `743 patent had already been reduced to practice, as a matter of law, no subsequent uses of the method could be experimental.

The court also rejected the argument that the testing of the drill bits was not a public use because it occurred underneath public land and was thus confidential. The court held that "secrecy alone is an ineffective gauge of experimentation."

Judge Dyk dissented, in his view, the testing of drill bits was not public because it occurred "under public land, hidden from view, and there has been no showing whatsoever that the use was anything but confidential." In addition, Judge Dyk viewed the use as experimental, finding the design of the drill bit and its method of use as so inextricably intertwined that testing of one necessarily implicates testing of the other.