Source: https://www.sandiegoiplaw.com/non-patent-patents/
Timestamp: 2019-04-21 03:09:45+00:00

Document:
The United States Patent and Trademark Office (USPTO) has an interesting history of what might informally be called non-patent patents. That is, legal provisions, or grants, that protect patentable subject matter, but with important limitations as compared to the exclusive rights afforded in a regular U.S. letters patent.
One such non-patent patent is the long-defunct patent caveat, instituted by the U.S. Patent Act of 1836. A caveat was a legal document similar to a patent application with a description of any “new art, machine, or improvement thereof” (U.S. Patent Act of 1836 § 12) and drawings, sans claims and examination. It was a notice (and cost $20 to file) to the Patent Office of an inventor’s intent to file a patent at a later date—“praying protection of his right till he shall have matured his invention” (U.S. Patent Act of 1836 § 12)— and had a shelf-life of one year, but could be renewed. A caveat was “filed in the confidential archives of the office, and preserved in secrecy” (U.S. Patent Act of 1836 § 12).
A modern version of the patent caveat is the provisional patent. Beginning June 8, 1995, the USPTO provided inventors with a provisional application (35 U.S.C. §111[b]), which requires the filing of a description (no claims required) and drawings where necessary for the understanding of the subject matter sought to be patented (35 U.S.C. § 113), to establish a filing date. A provisional application expires one year from the original filing date, and does not mature into an issued patent unless the inventor files a nonprovisional application before the expiration date. A provisional patent application is not examined and, unlike its predecessor, the caveat, the twelve-month period cannot be extended. A provisional application provides the means to establish an early filing date in a later-filed nonprovisional patent application filed under 35 U.S.C. §111(a) and does not count against the twenty-year patent term. It also allows an applicant to use the term “Patent Pending” when describing his or her invention.
The USPTO Defensive Publication Program, which provided for the publication of the abstract of the technical disclosure of a pending application if the applicant waived his or her rights to an enforceable patent, was available April 1968 to May 1985. A defensive publication offered limited protection by preventing others from later patenting the same invention, design, or plant. Such a publication was available to the public, and the applicant provisionally abandoned the application, retaining rights to an interference for a limited period of five years from the earliest effective U.S. filing date (MPEP 711.06).

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