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The grant of a patent is not always the last word that the Patent Office has on the subject. It is possible to instigate what is basically a patent recall, in which the Patent Office takes another look at the propriety of having issued the patent. Often, these are instigated by a third party who is unhappy with the constraints that the patent would impose. However, they can also be instigated by the patent’s owner.

These patent recalls are often referred to as “post-grant proceedings.” There are five varieties of post-grant proceedings:

  • Post-grant review
  • Inter partes review
  • Ex parte re-examination
  • Covered business method review
  • Supplemental examination

These differ in procedural details, the estoppel issues they raise, who can use them and when, and what issues can be considered. But all involve the Patent Office reconsidering its decision to issue the patent in the first place.

The first nine months of a patent’s life represent an open season for attacks based on grounds of invalidity. These attacks are carried out through Post-Grant Review. Using this procedure, the instigator, who is always a third party, can attack the patent not just based on prior art but also based on, for example, lack of written description, or failure to recite statutory subject matter.

For most patents (with the exception of certain “business method” patents), nine months of life confers immunity against attacks not based on prior art. In this case, the instigator uses the second of these procedures: Inter Partes review, to draw attention to prior art that may affect the validity of the patent. As the name “inter partes” would imply, only a third party can instigate this procedure.

Certain kinds of “business method” patents never acquire immunity from attacks based on grounds other than prior art. For these patents, the Patent Office has created the “Covered Business Method Review.” However, not just anybody can instigate Covered Business Method Review. The instigator must have either been sued or have reasonable apprehension of being sued based on that patent.

Ex parte re-examination can be instigated by either the patent owner or by a third party. However, as the term “ex parte” implies, the third party can only instigate; he cannot participate. A third party who wishes to rebut positions taken by the patent owner would have to use the “inter partes” procedure instead. Ex parte re-examination is most useful for patent owners who become aware of new prior art that may call the validity of their patent into question. Rather than address the matter during litigation, the patent owner may prefer to have the Patent Office consider it through this procedure.

There may be times when the patent owner would like to have the Patent Office consider the validity of a patent for issues other than prior art. Since ex-parte re-examination is limited to prior art, the Patent Office has provided another procedure: “Supplemental Examination.” This procedure is useful if the patent owner learns facts that may be used as a basis for an attack based on inequitable conduct. To immunize the patent against such an attack based on those facts, the patent owner would instigate Supplemental Examination. However, if, upon reviewing the facts, the Patent Office deems that a substantial new question of patentability has been raised based on prior art, it will transform the proceedings into Ex Parte Reexamination.

Contact us to find out how the attorneys at O&R can help you.