Patent reexamination is an often misunderstood term. Reexamination is
frequently viewed as a way to invalidate a competitor's patent(s).
While this may be true to some extent, reexamination is not easy or
inexpensive, and is often used by a patent holder to strengthen and
increase the value of their own patent.
Reexamination is a procedure by which the Patent Office may reconsider
the patentability of the claims of an issued patent. Reexamination
comes in two forms, ex parte reexamination and inter partes
Prior to getting into the intricacies of the ex parte and inter partes
reexamination, one must understand the two basic stages of either
reexamination process. The two-stage reexamination process was created
to ensure that system would not foster harassment of patent holders.
The first stage of the process simply determines whether a request for
reexamination rises to the level required for reexamination. This
requires that the prior art patents and printed publications submitted
with the request raise a "substantial new question of patentability."
The "substantial new question of patentability" protects patentees
from having to participate in unjustified reexaminations. If the
requirements of stage one are met, then the second stage begins
wherein actual reexamination takes place to determine if the claims
A patent owner or an interested third party may request ex parte
reexamination. Ex parte reexamination is unique in that once the
Patent Office determines that the requirements of stage one have been
met and actual reexamination, stage two, starts, the interested third
party is not permitted to file additional papers on the action.
Therefore, a third party requester has a very limited opportunity to
convince the Patent Office that certain claims should be found
invalid, while the patent holder has the entire reexamination process
to convince the Patent Office that the claims should be found valid.
Inter partes reexamination allows the interested third party to
participate in both stage one and stage two of the reexamination
process. Therefore, the third party has a greater opportunity to
convince the Patent Office that the claims are invalid by filing one
response following each patent owner's response to each office action.
It is important to note that the additional benefits of inter partes
reexamination come at a price. First, the inter party inter partes
reexamination requester cannot challenge the validity of any claim
that survives the reexamination. Secondly, the current filing fee for
inter partes reexamination, $8,800, is roughly 3.5 times the filing
fee for ex parte reexamination, $2,520.
Reexamination is an important offensive and defensive tool that should
be discussed with your patent attorney.