Public Use Bar: A Cautionary Tale for Innovators
For anyone in the world of Patents, the terms “public use” and “public disclosure” are critical—and often misunderstood. 35 U.S.C. § 102 defines these terms and their implications for patentability.
Grace Period
A key point to remember: the U.S. has a unique one-year grace period for filing a patent application after a public disclosure. In most other countries, any public disclosure can immediately bar you from obtaining a Patent. This is a crucial distinction that can make or break your intellectual property.
Defining the Public Use Bar
What exactly constitutes “public use bar”? Can a use be “public” even when it’s hidden from the public eye?
The U.S. Supreme Court’s 1881 decision in Egbert v. Lippmann (104 U.S. 333) provides a fascinating and enduring lesson. The inventor in this case created improved corset steels in 1855, giving them to a single individual to use. Even though the steels were never publicly seen, the Court ruled that this was a public use. The inventor’s subsequent patent, filed years later, was therefore invalidated.
The Egbert Court’s conclusions still stand as a stark warning:
- A single public use is enough. You don’t need to have a crowd of people using your invention to trigger the bar.
- Unrestricted use is public use. If you give or sell your invention to another person without any confidentiality agreements or restrictions, that use is considered public.
- However, experimental use is an exception. A use that is open to public view but is made in good faith solely for testing and experimental purposes does not count as a public use.
Egbert serves as a powerful reminder: the definition of “public use” is far broader than most people realize.
Protect Your Innovation
Don’t let a seemingly private action become a public forfeiture.
35 U.S.C. 102, in part, reads:
(a) Novelty; Prior Art.—A person shall be entitled to a patent unless—
(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention; or
(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
(b) Exceptions.—
(1) Disclosures made 1 year or less before the effective filing date of the claimed invention.—A disclosure made 1 year or less before the effective filing date of a claimed invention shall not be prior art to the claimed invention under subsection (a)(1) if—
(A) the disclosure was made by the inventor or joint inventor or by another who obtained the subject matter disclosed directly or indirectly from the inventor or a joint inventor; or
(B) the subject matter disclosed had, before such disclosure, been publicly disclosed by the inventor or a joint inventor or another who obtained the subject matter disclosed directly or indirectly from the inventor or a joint inventor.
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