Major changes to U.S. patent law arose from GATT Uruguay Round implementing legislation.
Detailed information can be found at:
http://www.patentsusa.com/19950608_20_year_term.html ;
http://www.patentsusa.com/19950608_GATT.pdf; and
http://www.patentsusa.com/19950608_Presentation.pdf
These changes were significant in that they marked an end to 17 year patent term. Prior to enactment of these changes, patent term was 17 years from the issue date of a patent and continuations and divisionals had terms of 17 years from their issue dates (subject to any terminal disclaimers). After the rule changes, patent term begins on grant but runs 20 years measured from the filing date of a patent application. If continuations or divisionals are filed, their term is measured from the filing date of the parent application.
Design patents were not affected.
Patents that were in force or that would issue on an application filed before June 8, 1995 were given a term that was the greater of the 20 year from filing or 17 year from grant.
Applications filed on or before June 8, 1995 with an effective U.S. filing date prior to June 9, 1992 were given a transition restriction requirement. For those applications, no restriction would be made or maintained except in certain circumstances, such as where the requirement was made prior to April 8, 1995.
Another significant change that resulted from these changes is that provisional patent applications were established. They would provide a domestic priority system to give U.S. applicants the same potential term as foreign applicants. Provisional patent applications are still in use.
These provisional patent applications never issue into a patent, and can never be enforced. If a regular, complete, patent application is prepared and filed within a year from the filing date of the provisional patent application, the regular patent application may be entitled to the filing date of the provisional patent application. The maximum term of any patent that eventually issues will be twenty years from the filing date of the regular patent application (the up to one year period while the provisional application was pending is not counted).
One of the purposes of provisional patent applications was to put U.S. inventors on equal footing with foreign inventors who file in the U.S. Under the Paris Convention, an international treaty, within a year after the foreign inventors file their patent applications in their home country, they can file a U.S. patent application and be entitled to the filing date in their home country. The term of their U.S. patent will be twenty years from filing in the U.S. (the up to one year period after they filed in their home country but before they filed in the U.S. is not counted).
The provisional patent applications have the same effect. An actual U.S. patent application can be filed up to one year from the filing date of a U.S. provisional application, and still be entitled to the filing date of the U.S. provisional application, but the 20 years from filing will be based on the filing date of the actual application, not the provisional application.
The provisional applications were suggested to be potentially useful in obtaining an earlier filing date than would otherwise be possible. However, in order to be valid, the provisional application must comply with the first paragraph of section 112 of the patent law. If the provisional application does not comply with this section, it will be invalid and will not provide a filing date.
As the U.S. Patent and Trademark Office does not examine these applications, it may not become apparent that a provisional application is invalid until after the deadline for filing a patent application has passed. Provisional applications automatically expire one year after filing, and that this deadline is not extendible. Foreign applications must be filed within one year of the filing date of the provisional application in order to be entitled to the filing date of the provisional application. Thus, a disadvantage of provisional applications is that there is no opportunity to receive a first examination by the U.S. Patent and Trademark Office before making the decision of whether or not to file corresponding foreign applications.
Some patent term extensions for delays due to appeals, interferences, and secrecy orders were also provided.
35 U.S.C. 104 was amended to allow invention dates to be established in WTO countries (effective January 1, 1996). Since December 8, 1993, invention dates could be established in NAFTA countries.
37 CFR 1.131 was also amended to allow the use of facts showing completion of an invention in a WTO member country.
The effective date for the change in patent term to 20 years from filing, and for the ability to use provisional applications, was June 8, 1995.