Experimental use preempts public use, on-sale bars to patentability
Common sense might seem to dictate that a new invention would require testing before an inventor moves ahead with it. But could such testing trigger the public use or on-sale bar to patentability? Not necessarily. As the U.S. Court of Appeals for the Federal Circuit explained in a recent case, the experimental use exception may negate both bars.
Jury backs inventor
The case involves two patents for methods and systems for correcting spinal column anomalies, such as those caused by scoliosis, by applying force to multiple vertebrae simultaneously. A surgeon was the sole inventor on both patents.
The surgeon used the invention in three surgeries treating the three most common types of scoliosis-caused spinal deviation conditions more than a year before he filed the patent application. After the three-month acute phase of recovery, the patients returned for follow-up appointments during which the doctor viewed X-rays to determine whether the surgery had corrected the curvatures. Two of these follow-ups also occurred more than one year before the filing of the application on December 30, 2004.
The surgeon subsequently sued Medtronic for infringement of his patents. The jury found in his favor and awarded almost $18 million in damages. Medtronic appealed, arguing, among other things, that the patents were invalid because of the public use and on-sale bars in Section 102(a) of the Patent Act.
The public use bar is triggered when an invention is ready for patenting and in public use before the critical date. The on-sale bar applies if an invention is ready for patenting and the subject of a commercial offer for sale before the critical date.
The critical date under the applicable law for this case was one year before the date of application filing. Under current law, the critical date is the application date, but a one-year grace period is allowed for a public use or commercial offer for sale by the inventor.
Court doesn’t back down
On appeal, Medtronic asserted that the two surgeries that preceded the critical date triggered the public use and on-sale bars. The court acknowledged that an inventor’s own prior commercial use — even if kept secret — can constitute a public use or sale, barring the inventor from obtaining a patent. But it concluded that these surgeries fell within the experimental use exception.
The court explained that a use is experimental if its purpose is to:
Test claimed features of the invention, or
Determine whether the invention will work for its intended purpose.
The experimental use inquiry asks whether the inventor’s conduct would lead the public to reasonably believe the invention was in the public domain. If not, the exception generally applies.
According to the court, the evidence in this case pointed toward a finding of experimental use. For example, the surgeon wasn’t certain the device would work on different types of scoliosis, so he performed surgeries on the three main types. He wasn’t confident the new procedure was effective until the follow-up appointment for the third of those surgeries.
The Federal Circuit further noted that the surgeon had earned no more from the surgeries than he would have earned using existing methods, nor had he attracted the three patients because of the new technique, as they were unaware it was being used. And others in attendance at the procedures were aware he was experimenting.
Moreover, the surgeon didn’t surrender control of the invention before the critical date. He was the only person to perform the method with his device, and very few of the others in attendance had a clear view of the surgical field. He also maintained control through the expectation of secrecy binding the other medical professionals who were present at the surgeries.
The court dismissed Medtronic’s claim that the fact that the surgeon had charged for the three procedures weighed against a finding of experimental use. Because the inventor had earned no more from the surgeries than he would have using prior-art methods and had not attracted his patients based on use of the inventive method, the court concluded that his fee could be viewed as incidental to experimental work. (See “When is a use ‘experimental’?” for factors indicating a use is experimental.)
Federal Circuit supports testing
The Federal Circuit’s findings regarding the experimental use exception suggest the court recognizes the need for testing in certain circumstances. It was reasonable, the court said, to engage in testing for a brief time on a small but representative range of expected circumstances of use and to rely on follow-up to determine whether the method worked.
Barry v. Medtronic, Inc., No. 17-2463, Jan. 24, 2019, Fed. Cir.
When is a use “experimental”?
The Federal Circuit in Barry v. Medtronic, Inc. (see main article) enumerated a host of factors that courts might find relevant when determining whether a use of an invention is experimental, including:
But the court cautioned that, while many of these factors are fact-based, experimental use nonetheless is a question of law. This means a judge will resolve the issue based on legal principles, rather than a jury determining the issue based on evidence.