Prior art, in most systems of patent law, constitutes all information that
has been made available to the public in any form before a given date that might
be relevant to a patent's claims of originality. If an invention has been
described in the prior art, a patent on that invention is not valid.
Information kept secret, for instance, as a trade secret, is not usually prior
art, provided that employees and others with access to the information are under
a non-disclosure obligation. With such an obligation, the information is
typically not regarded as prior art. Therefore, a patent may be granted on an
invention, although someone else already knew of the invention. A person who used
an invention in secret may in some jurisdictions be able to claim "prior
user rights" and thereby gain the right to continue using the invention. As a
special exception, earlier-filed and unpublished patent applications do
qualify as prior art as of their filing date in certain circumstances.
To anticipate the subject-matter of a patent claim, prior art is generally
expected to provide a description sufficient to inform an average worker
in the field of some subject matter falling within the scope of the claim.
Prior art must be available in some way to the public, and in many countries,
the information needs to be recorded in a fixed form somehow. Prior art
generally does not include unpublished work or mere conversations EPC). It is
disputed whether traditional knowledge constitutes prior art.
Patents disclose to society how an invention is practiced, in return for
the right to exclude others from manufacturing, selling, offering for
sale or using the patented invention without the patentee's permission.
Patent offices deal with prior art searches in the context of the patent
granting procedure. Usage in litigation
Arguments claiming prior art are used in defending and attacking patent validity.
In one U.S. case on the issue, the court said:
"One attacking the validity of a patent must present clear and convincing
evidence establishing facts that lead to the legal conclusion of invalidity. 35
U.S.C. § 282. To establish invalidity under 35 U.S.C. § 103, certain factual
predicates are required before the legal conclusion of obviousness or
nonobviousness can be reached. The underlying factual determinations to be
made are (1) the scope and content of the prior
art; (2) the differences between the claimed
invention and the prior art; (3) the level of ordinary skill in the
art; and (4) objective evidence of
non-obviousness, such as commercial success, long-felt but unsolved need,
failure of others, copying, and unexpected results."
Graham v. John Deere Co., 383 U.S. 1, 17, 148 USPQ 459, 467.
Types of prior art searches = Novelty=
A "novelty search" is a prior art search that is often conducted by patent
attorneys, patent agents or professional patent searchers before an inventor
files a patent application. A novelty search helps an inventor to determine if
the invention is novel before the inventor commits the resources necessary
to obtain a patent. The search may include searching in databases of
patents, patent applications and other documents such as utility models and in
the scientific literature. Novelty searches can also be used to help an
inventor determine what is unique about his/her invention. Anything not found in
the prior art can be potentially patentable. Thomas Edison, for example,
did not get a patent on the basic concept of the light bulb. It was
already patented and therefore in the prior art. Instead, Edison got a patent
on his improvements to the light bulb. These improvements included a very thin
filament and a reliable technique for joining the white hot filament to the
room temperature lead wires. A novelty is also conducted by patent
examiners during prosecution of the patent application. For instance,
examiner's search guidelines applicable to the United States are found in the
U.S. Manual of Patent Examining Procedure 904.02 General Search
Guidelines, Prior Art, Classification, and Search.
= Validity= A "validity search" is a prior art
search done after a patent issues. The purpose of a validity search is to find
prior art that the patent examiner overlooked so that a patent can be
declared invalid. This might be done by an entity infringing, or potentially
infringing, the patent, or it might be done by a patent owner or other entity
that has a financial stake in a patent to confirm the validity of a patent.
Crowdsourcing, where a large number of interested people search for prior art,
may be effective where references would otherwise be difficult to find.
= Clearance= A clearance search is a search of issued
patents to see if a given product or process violates someone else's existing
patent. If so, then a validity search may be done to try to find prior art
that would invalidate the patent. A clearance search is a search targeting
patents being in force and may be limited to a particular country and
group of countries, or a specific market.
Duty of disclosure In the United States, inventors and
their patent agents or attorneys are required by law to submit any references
they are aware of to the United States Patent and Trademark Office that may be
material to the patentability of the claims in a patent application they have
filed. The patent examiner will then determine if the references qualify as
"prior art" and may then take them into account when examining the patent
application. If the attorney/agent or inventor fails to properly disclose the
potentially relevant references they are aware of, then a patent can be found
invalid for inequitable conduct. Japan also has a duty of disclosure.
Australia has abolished its duty of disclosure with regard to the results of
documentary searches by, or on behalf of, foreign patent offices, except
where: (a) normal exam was requested before
April 22, 2007, (b) the foreign patent office search
issued before April 22, 2007, and (c) acceptance was officially advertised
before July 22, 2007. Public participation in patent
examination With the advent of the Internet, a
number of initiatives have been undertaken to create a forum where the
public at large can participate in prior art searches. These forums have been
related to both issued patents and pending patent applications.
= Pending patent applications= More recently, different attempts to
employ open Internet-based discussions for encouraging public participation
commenting on pending U.S. applications have been started. These may take the
form of a wiki: Peer-to-patent online system for open,
community patent review. Wikipatents. Public patent clarity: the
public can add prior art references for a given patent.
patents@stackexchange. A Q&A site for people interested in improving and
participating in the patent system. Patent examiners often use the online
encyclopedia Wikipedia as a reference to get an overall feel for a given subject.
Citations of Wikipedia as actual prior art can be problematic, however, due to
the fluid and open nature of its editing, and Patents Commissioner Doll
said the agency used Wikipedia entries as background and not as a basis for
accepting or rejecting an application. See also
Defensive publication Illegal number, illegal prime
Information disclosure statement Internet as a source of prior art
Micropatent Non-binding opinion
Patent classification Patent watch
Priority right Public participation in patent
examination Search report
= Notable prior art databases= Espacenet—European Patent Office public
patent literature database, with patents from many patent offices.
Google Patents—public search engine from Google that indexes patents from the
United States Patent and Trademark Office and other international patent
offices, and machine-CPC-classified non-patent literature from Google
Scholar. For other patent search services, see
Category:Patent search services. The Internet Archive Wayback Machine is
recognized by the USPTO as a valid source of prior art on the Internet,
though generally the date of archiving is considered the first published date,
rather than the date on any documents that have been archived.
References Further reading
Blenko, Walter J., Considering What Constitutes Prior Art in the United
States, JOM, 43, p. 45. Retrieved 2012-01-27.
External links = Official institutions=
World Intellectual Property Organization PatentScope, WIPO search tool for
international and national patent collections.
WIPO Gold, Search national patent offices including US, Japan, the UK, and
others. A free public search tool gateway for WIPO's global collections of
searchable IP data." United States Patent and Trademark
Office Patent Application Information
Retrieval, the USPTO search engine for patent and patent application file
histories displays reasons why patents are issued; search by application number
or customer number. Seven Step Strategy, USPTO patent search
strategy. European Patent Office
Guidelines for Examination in the EPO, section b.vi
Guidelines for Examination in the EPO, section g.iv
Legal Research Service for the Boards of Appeal, European Patent Office, Case Law
of the Boards of Appeal of the EPO, i.c.1 : "Defining the state of the art"