The On-Sale Bar to Patentability
by Glenn R. Smith
Section 102 of the patent statutes, found under Title 35 of the United States Code, lists several "Conditions for patentability." Within this section, there are listed what are known as bars to patentability. Included is the so-called "on-sale bar."
A person shall be entitled to a patent unless . . . the invention was . . . on sale in this country more than one year prior to the date of the application for patent in the United States.
35 U.S.C. § 102(b). That is, an inventor has a one year grace period to file a patent application from the date the invention was on sale in the US. One year prior to the filing date is termed the "critical date."
The U.S. Supreme Court recently specified a two-part test for application of the on-sale bar in Pfaff v. Wells Elecs., Inc. 1998 U.S. LEXIS 7268 [48 USPQ2d 1641] (Nov. 10, 1998). First, the product must be the subject of a commercial offer for sale. Second, the invention must be ready for patenting. Both of these conditions must exist before the critical date. With respect to the second condition, the court in Pfaff required either proof of "reduction to practice" or proof that the inventor prepared drawings or other descriptions of the invention sufficiently specific to enable a person skilled in the art to practice the invention. That is, reduction to practice was sufficient but not necessary to meet the "ready for patenting" condition.
As an aside, the meaning of the term "reduction to practice" depends on the invention: successful performance of a process; assembly, adjustment and use of a machine; a completely manufactured article of manufacture; or a completely composed composition of matter.
In the past, the Federal Circuit balanced various polices against all of the circumstances surrounding the sale or offer to sell, including the stage of development and nature of the invention, in order to determine when the on-sale bar was triggered. See e.g. Micro Chemical, Inc. v. Great Plains Chemical Co., 103 F.3d 1538, 1544 (Fed. Cir. 1977). After the decision in Pfaff, however, the Federal Circuit will apply the Supreme Court two-part test without this "totality of the circumstances" consideration. See Weatherchem Corp. v. J. L. Clark Inc., 49 USPQ2d 1001, 1006 (Fed. Cir. 1998).
For example, in Pfaff, detailed engineering drawings of a computer chip socket that resulted in a purchase order from Texas Instruments before the critical date was sufficient to trigger the on-sale bar, despite the fact that no prototypes were built before the critical date. As another example, in Weatherchem, an order for "shake and spoon" spice caps placed before the critical date, based on a Weatherchem quote, in addition to drawings made before the critical date that contained each limitation of the patent claims, was sufficient to invalidate the patent. The court in Weatherchem considered continued fine-tuning of the cap design after the critical date as irrelevant.
Although this article addresses only the on-sale bar, it is very important for an inventor to consult an attorney regarding all acts related to sales, offers for sale, public use, publications and other disclosures associated with an invention, which may result in an immediate or subsequent loss of foreign or domestic patent rights.