Reexaminations provide a means for patent owners or third parties to request
that the Patent Office reexamine patent claims in light of a "substantial
new question of patentability" that casts doubt upon the validity of the
issued claims.

Defending a Patent litigation lawsuit can be very costly, both in time and
money. For example, a patent lawsuit can require several years of complex
litigation to complete pretrial discovery and trial. Then, the trial may be
followed by an appeal to the Federal Circuit Court of Appeals. Thus, Patent
Reexaminations can provide a cost-effective alternative to patent litigation
and should be considered at the outset and part of the patent litigation
strategy.

Although a myriad of defenses can be raised by an accused infringer in a
patent litigation case, the main defenses consist of (1) Proving that the
Patent at Issue is invalid based upon prior art and thus not enforceable;
and/or (2) Proving that the accused product is not infringing the claims of the
Patent at Issue.

As will be explained below, patent validity may be resolved in the
reexamination process and, also, the scope of the patent claims may be altered.

Ex Parte Reexamination

In an Ex Parte reexamination, either a challenger or patent holder
may seek reexamination of a patent based on patents or printed publications.[1] The requester files the request for
reexamination and within three months the PTO determines whether a substantial
new question of patentability exists.[2] If so, the PTO orders reexamination of
the patent.[3] A determination that there is no
substantial new question is final and non-appealable.[4]

If the PTO orders reexamination, the patent holder is given the opportunity
to file a statement concerning the new question of patentability, including
amendments or new claims they want to propose[5] (provided, however, that the claims may
not be broadened).[6] If the patent holder files such a
statement, the statement must be served on the person requesting reexamination,
and the requester is given two months to file a reply to the patent owner's
statement.[7] From that point on, the claims are
examined without participation by the requester. Following the Ex Parte
reexamination, the PTO issues a certificate canceling any claim determined to
be unpatentable, confirming any claim determined to be patentable and
incorporating in the patent any new claim or amended claim determined to be
patentable.[8]

Inter Partes Reexamination

Inter Partes reexaminations are similar to Ex Parte
proceedings in some ways. Both are initiated by a request for reexamination.[9] Also, the only ground for seeking
reexamination under either process is prior art consisting of patents or
printed publications.[10] Furthermore, at the outset, the PTO
determines whether the request raises a substantial new question of
patentability.[11]

If the PTO determines that there is a substantial new question of
patentability, an Inter Partes reexamination is ordered.[12] Thereafter, just as in an Ex Parte
proceeding, the third-party requester will be provided with a copy of Office
Actions issued by the PTO.[13] Also, just as in an Ex Parte
proceeding, the third-party requester will be provided a copy of the patent
owner's responses to Office Actions. However, unlike an Ex Parte
proceeding, the third-party requester may reply to the Office Actions and to
the patent owner's responses.[14]

After the Examiner has reached a final decision in an Inter Partes
proceeding, either the patent owner or the requester may appeal an adverse
finding to the PTO Board of Patent Appeals and Interferences (Board). After the
Board reaches its decision, either party may appeal to the U.S. Court of
Appeals for the Federal Circuit from an adverse determination (Court).[15] On the other hand, in an Ex Parte
case, the requester does not have comparable options of appeal either to the
Board or to the Court.

A critical difference between Inter Partes and Ex Parte
proceedings concerns estoppel. Unlike an Ex Parte requester, the Inter
Partes requester will be estopped in subsequent litigation in a district
court or a subsequent Inter Partes proceeding to assert the invalidity
of any claim finally determined to be valid on any ground which is raised or
could have been raised in the Inter Partes reexamination.[16]

Reexaminations- Advantages and Disadvantages

The cost of a reexamination proceeding to a third-party
requester may be a small fraction of the cost of litigation. A reexamination
may also provide for a quicker determination of the effects of the prior art.
In addition, a third-party may request reexamination of a patent without
engaging in any allegedly or potentially infringing commercial activity. This
allows a patent owner to test the validity of a patent's claims before
expending substantial resources to develop a product or process that might
later be found to infringe. In addition, unlike litigation, patents are not
presumed valid in inter partes reexamination. Therefore, a third party does not
have to provide “clear and convincing” proof to invalidate a patent.

However, reexaminations have significant limitations:

• some issues of patentability
  that can be considered in litigation, such as the adequacy of a patent's
  written description, compliance with the "best mode" requirement,
  or bars arising from prior public use or commercialization cannot be
  considered in a reexamination;
• a reexamination is limited to
  considering documentary prior art (patents and printed publications);
• unlike court proceedings,
  reexamination does not allow for subpoenas, interrogatories, depositions,
  or live testimony and cross-examination of witnesses;
• an inter partes reexamination
  can create an "estoppel," preventing the requesting party from
  raising arguments in litigation that could have been raised in the
  reexamination.
• Inter partes reexaminations
  are only available for reexamination of patents filed on or after Nov. 29,
  1999. Hence inter partes process is unavailable to challenge a substantial
  number of patents.

Most importantly, a reexamination that does not invalidate
or significantly narrow the claims of a patent can leave the patent stronger
than before. Thus, it should be used only in limited circumstances.

Inter-Partes vs.
Ex-Partes

In both Ex Parte and Inter Partes proceedings, the patent challenger
has the opportunity to submit prior art for consideration by the Examiner. The
patent challenger, of course, has the ability to do a thorough search of the
prior art to find art that may be used to invalidate the patent or limit the
scope of the claims so the challenger's product does not infringe.

Whether to pursue patent reexamination, either Inter Partes or Ex
Parte, involves the balancing of significant considerations. The major
advantage to a patent challenger of the Inter Partes procedure over the Ex
Parte procedure is that in the Inter Partes procedure the challenger
has the right to participate throughout the process – for example, by
supplying prior art and by filing rebuttals to arguments submitted by the
patentee. Also, the challenger can submit arguments supporting the Examiner
when the Examiner takes a position unfavorable to the patentee, and the
challenger can submit declarations by technical experts concerning the patent
and the prior art.

The costs of filing of a patent reexamination should also be considered.
Currently, the USPTO fee to file an ex-parte reexamination is $2520.00 as
opposed to $8800.00 for an inter-partes reexamination, exclusive of legal fees.

The challenger however, must consider certain disadvantages to the reexamination
process. One important consideration is that the process gives the patentee the
opportunity to amend its claims and add new claims. While the patentee may not
broaden the scope of its claims, the patentee may amend the claims to (1) make
them patentable in view of the prior art, including the new prior art cited by
the challenger, and (2) make them more clearly cover the challenger's allegedly
infringing product. Another major disadvantage to the challenger, in the Inter
Partes process, is that the challenger is estopped from challenging the
patent in court, except in very limited circumstances. Thus, the Inter
Partes challenger must be prepared to do its best job before the PTO
because it is unlikely to get another opportunity if it fails to achieve the
results it desires there.

Reexaminations Effect on Staying
Patent Litigation

Whether the initiation of a patent reexamination stays a currently active
patent litigation case varies from jurisdiction to jurisdiction and is at the
discretion of the court. However, it is well documented that on average, courts
tend to stay the litigation in inter-partes reexaminations more often than
ex-parte reexaminations due mainly to the potential estoppel issues that are
raised in an inter-partes reexamination.

Conclusion

In summary, though often times aggressively defending a patent infringement
claim in federal court is the best approach, the advantages and disadvantages
of patent reexaminations should be at least considered at the outset of the
case as a possible alternative cost-effective approach.

John D. Tran is a registered Patent Attorney before
the USPTO and is a partner at the firm of Ardent Law Group, P.C.. Mr. Tran
specializes in all aspects of Intellectual Property, including litigation, and
patent, trademark & copyright registration matters. He devotes a
significant portion of his practice assisting businesses and companies develop,
maintain and protect their intellectual property portfolio. He can be reached
via his email at jtran@ardentlawgroup.com 
For more information www.ardentlawgroup.com

Endnotes
1. 35 U.S.C. §§ 301, 302, 37 CFR §1.510
2. 35 U.S.C. §§ 303, 37 CFR §1.515
3. 35 U.S.C. § 304, 37 CFR §1.525
4. 35 U.S.C. § 303
5. 35 U.S.C. §§ 304, 305, 37 CFR §1.530(b)
6. 35 U.S.C. § 305
7. 35 U.S.C. §§ 304, 37 CFR §1.535
8. 35 U.S.C. § 307, 37 CFR § 1.570
9. 35 U.S.C. §§ 302, 311(a), 37 CFR §§ 1.510, 1.913
10. 3 Id.
11. 35 U.S.C. §§ 303, 312(a), 37 CFR §§ 1.513, 1.931
12. 35 U.S.C. §313, 37 CFR §1.931
13. 35 U.S.C. §314(b), 37 CFR §1.903
14. 35 U.S.C. §314(b), 37 CFR §1.947
15. 35 U.S.C. §315, 37 CFR §1.959
16. 35 U.S.C. §§ 315(c), 317(b)