WEB PATENT NEWS--February, 1999

by Robert M. Hunter, Registered Patent Agent

News about patents, licensing and seed capital sources for inventors and innovating organizations.


On November 10, 1998, the U.S. Supreme Court fired a warning shot over the bow of inventors racing to commercialize their inventions. In Pfaff v. Wells Electronics Inc., the Court settled the question of whether an invention must be "reduced to practice" before an offer to sell the invention is made that can trigger a statutory bar to patentability.

U.S. patent law [U.S.C. 102(b)] bars the issuance of a patent to an inventor who files his U.S. patent application more than one year after he began selling his invention or offering it for sale in the U.S. Thus, a valid patent cannot be obtained on a claimed invention that was offered for sale before a "critical date" that is one year before the filing date of a U.S. patent application that adequately discloses the invention.

U.S. patent law bars the issuance of a patent to an inventor who files his U.S. patent application more than one year after he began selling his invention or offering it for sale in the U.S.

Some previous lower court decisions had held that an invention must have been "reduced to practice" before an offer to sell can trigger the beginning of the one-year "grace period." The term "reduced to practice" was borrowed from interference case law in which "priority of invention" contests among alleged inventors were decided by the courts. The term generally means that the invention must be complete enough to have been described in a patent application (constructive reduction to practice) or built and tested under conditions similar to those that would occur in actual use (actual reduction to practice, the meaning used in this instance).

In Pfaff v. Wells Electronics Inc., the Supreme Court decided that the on-sale bar applies when two conditions are satisfied before the critical date. First, a product embodying the invention must be the subject of a commercial offer for sale, which all parties agreed had occurred in the Pfaff case. Second, the invention must be "ready for patenting." The Court determined that the latter condition may be satisfied in at least two ways: "by proof of reduction to practice before the critical date; or by proof that prior to the critical date the inventor had prepared drawings or other descriptions of the invention that were sufficiently specific to enable a person skilled in the art to practice the invention." Because the latter condition was satisfied in the second way in the Pfaff case (because drawings sent to a manufacturer before the critical date fully disclosed the invention), the Pfaff patent (U.S. Patent No. 4,491,377) was declared invalid and his patent infringement suit against an alleged infringer was unsuccessful.

The on-sale bar applies when both (1) a product embodying the invention is offered for sale in the U.S. before the critical date and (2) the invention is ready for patenting before the critical date.

The lesson that this decision teaches is that delay in filing a patent application after commercialization activities have begun can be fatal to an attempt to obtain a valid U.S. patent. If an inventor's conception of an invention is complete (the invention is "ready for patenting") and a sale or offer to sell a product embodying the invention is made (even if the sale or offer to sell is made under an agreement of confidentiality), the one-year grace period for filing a U.S. patent application on the invention begins. Failure to file during the one-year grace period bars patentability in the U.S. While an offer to assign an invention is not considered an offer to sell an invention and does not trigger the on-sale bar, countries other than the U.S. have even more stringent restrictions on commercialization activities that occur before a patent application is filed. If an invention has commercial potential and U.S. patent protection is considered appropriate, the timely filing of a U.S. patent application is a must. Filing of a provisional U.S. patent application that adequately discloses the invention you want to claim is a relatively quick and inexpensive way to safeguard patentability in the U.S.


The U.S. Patent and Trademark Office (USPTO) is soliciting comments from the public as it develops its Internet Usage Policy. U.S. patent law requires that applications for patent be kept in confidence by the USPTO. In its Request for Comments, the USPTO indicates that it is considering using "Digital IDs," a technology that allows secure, authenticated, time-stamped communication via e-mail and forms on the Web.

Digital IDs can be purchased from companies like VeriSign at a cost of less than $10 per year. They allow individual users of popular e-mail client applications like Microsoft Outlook, Netscape Communicator/Messenger and Eudora to digitally sign a message so a recipient knows that it really came from the sender and to encrypt a message so that only the intended recipient can decrypt and read its contents and attachments.


The SBIR programs of the larger Federal Government departments and agencies are an excellent source of seed capital for small business technology development projects. Links to helpful SBIR sites are available on the Web Patent web site.

If you have any questions about patents or U.S. Government funding for technology research and development, please contact us. If you wish to be removed from this mailing list, please let us know.

Robert M. (Bob) Hunter, Ph.D., P.E.
Registered Patent Agent
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