A patent is a right granted under U.S. law that allows the patent
owner to exclude others from making, using, selling, offering for sale, or
importing the patented invention and without the inventor’s permission
for a fixed term. Generally, this term extends for 14 years for a plant patent; 20 years for other types of
patents, from the time of filing the patent application. Any activity involving
the patented invention which violates these rights is said to infringe the patent.
The patent owner may bring a lawsuit for infringement to collect monetary damages and
to stop the infringing activity. There are several defenses to patent
infringement. One defense is the Doctrine of Intervening Rights. Another
defense, which will completely insulate an alleged infringer from liability, is
Doctrine of Intervening Rights
United States patent law allows a patentee to request a reissue of a patent,
a procedure used when a patent, as issued, needs to be corrected. There may be
an error in the specification that undermines the validity of the patent, or a
patentee may determine that the scope of the patent, as issued, is narrower or
broader than intended. As long as the error occurred without deceptive
intention, the patentee may seek a reissue of the patent.
Once issued, the patent is publicly known and relied upon to disclose what
is claimed within the patent by the inventor as the subject of his invention.
If a patent is changed in such a way that the original disclosure does not
disclose certain features of the later claimed invention, the patent laws
protect those who in good faith relied on the scope of the patent as originally
issued in making, using, or selling some invention or process. These users are
said to have acquired intervening rights. If such use of the invention or
process was not covered by the patent as originally issued, the statute
protects that use. In such a case, a court has no discretion and must find that
there is no infringement on the basis of the absolute intervening rights. Even
if a person or business has not used the invention but has made substantial
preparation towards making, using or selling it prior to the patent’s reissue,
equitable intervening rights may still be found. In contrast to absolute
intervening rights, a court will determine whether there has been a sufficient
investment of time and money to find that equitable intervening rights have
been obtained that justify protecting the investment by finding that no
infringement of the reissued patent has occurred.
A similar situation occurs when a patentee seeks a reexamination of a
patent. In such a case, the patentee or a third party may discover evidence
that a patent is not valid and wish to amend the claim in order to obtain
patent protection or obtain a ruling from the United States Patent and
Trademark Office (USPTO) that the claim as set out in the patent is valid. If
the patent, as re-examined ,contains a patentable new claim, intervening rights
will protect the use or substantial preparation for the use of a process or
invention not covered by the original patent in the same way as with a reissued
The final way in which intervening rights may be established is when utility
patent maintenance fees are not paid on time or within the six-month grace
period following the due dates for those fees, which are payable at three
different times over the life of a 20-year utility patent. Although the USPTO
allows a patentee of an expired patent to petition the USPTO to reinstate a
patent when failure to pay maintenance fees on time was unintentional or
unavoidable, the law protects persons, who relied on the presumption that the
patent had been abandoned, to use, make or sell the subject of the expired
patent or to make substantial preparations to use it. In such cases,
intervening rights will be found to have been established in the same manner as
in re-issued and re-examined patents.
Patent law is designed to encourage the disclosure of new inventions and
technologies by providing the inventor with an incentive–the exclusive right
in the invention–in exchange for making the details of the invention available
to the public in the form of the patent application and the issued patent.
Because the granting of exclusive rights runs contrary to cherished free-market
principles, the federal government strictly limits the patent. An attempt by a
patent owner to expand the scope of the exclusive rights granted by a patent
may be found to have misused the patent, which will prevent the patent owner
from prevailing in a patent infringement action.
One of the ways that a patent owner can improperly expand the scope of a
patent right is through a tying arrangement, which is where the patent owner
conditions the sale of the patented product or the licensing of the patent on
the sale of some other product that is not protected by any patent or on the
sale of a product or license under a completely different patent. Whether a
tying arrangement will actually be found to constitute misuse will depend upon
an analysis of the relationship between the patent and the tied product and
whether the patent owner has market power in the market for the patented
product. If the patent owner does not have market power in the market for the
patented product, which is to say that prospective purchasers of the patented
product have other options, the tying arrangement will not be found to be
anticompetitive or to constitute misuse of the patent.
Another form of patent misuse is an attempt to extend the term of a patent.
Although United States contract law is extremely liberal as to what parties may
contract to, a contract to pay patent royalties beyond the statutory term of a
patent, or any other mechanism for extending the term of a patent, constitutes
patent misuse. This absolute enforcement of the statutory 20-year patent term
is in keeping with the main purpose of patent law, which is to make new ideas
available to the public and advance science and technology.
Patent misuse does not render a patent invalid. Although an alleged
infringer will not be liable for infringement during the period of patent
misuse, cessation of the misuse of the patent renders the patent fully
effective against future or continued infringing activities.