Inter Partes Review
An Inter Partes Review (IPR) is a proceeding initiated at the United States Patent Office in order to challenge the validity of a US patent based on printed publications. The District Court will typically stay the court proceedings until the conclusion of the IPR, particularly if the IPR is filed early in the litigation (e.g., after filing the Answer). If the result of the IPR is to invalidate some or all of the claims in the patent, these claims are effectively withdrawn from the District Court case. Below is an overview of the stages of an IPR proceeding:
Post-Issuance: During the nine months after issuance, a patent can be challenged using the Post Grant Review procedure, and thereafter it can be challenged using the Inter Partes Review (IPR). If a complaint for patent infringement has been filed in a district court, an IPR petition must be filed within 12 months of the filing date of the complaint (or lose the right to file an IPR petition).
IPR Petition: The IPR petition is filed based on prior art not considered by the patent examiner during prosecution of the patent application. The IPR petition must include copies of the relied upon prior art. The IPR petition may also include a declaration from an expert in the field supporting the grounds for the review.
Filing Date Accorded: After the IPR petition is filed, the patent office will review the IPR petition to verify it is complete and complies with all regulatory requirements. A filing date will not be accorded if the IPR petition is incomplete § 42.106(a)(b). If the IPR petition is complete but contains errors, a filing date will be accorded but the petitioner must correct the errors within a specified deadline. It typically takes around two to four weeks for the patent office to review the IPR petition and accord a filing date (if complete).
Discovery Agreement: The parties may file an agreement as to discovery of the initial disclosures (e.g., an agreement that declarants relied on by either party may be automatically deposed without motioning the PTAB). The agreement must be filed prior to the PO Preliminary Response.
Patent Owner (PO) Preliminary Response: The PO's preliminary response is due three months after the filing date for the IPR petition has been accorded by the patent office. The PO's preliminary response includes arguments as to why the IPR petition should be denied (not instituted), such as the prior art does not anticipate or render the claims obvious, or the prior art was either considered by the examiner or essentially the same as the prior art considered by the examiner during prosecution.
Decision on Petition: The PTAB will consider the petition and preliminary response and either deny or grant the petition, with the entire petition phase not exceeding six months. A decision to institute a trial will typically include an analysis of the strengths and weaknesses of all challenges in the petition in order to provide guidance to the parties for the upcoming trial. A party dissatisfied with the Board’s determination to institute (or not institute) a trial may request rehearing as to points believed to have been overlooked or misapprehended.
PO Discovery: If the petition is granted (the IPR instituted), the PO is given three months for discovery which typically means deposing any declarants relied on in the IPR petition.
PO Response and Motion to Amend: The PO files a response to the petition (which may include a declaration from an expert in the field) and may optionally file a motion to amend the claims. For example, the PO may file claim amendments that attempt to avoid the prior art cited in the IPR petition.
Petitioner Discovery: The Petitioner is given three months for discover which typically means deposing any declarants relied on in the PO Response.
Petitioner's Reply to PO Response and Opposition to Amended Claims: The Petitioner files a Reply to the PO Response together with arguments against the patentability of any amended claims (which is not limited to arguments based on prior art).
PO Supplemental Discovery: The PO is given one month to perform supplemental discovery which typically means deposing any declarants relied on in the Petitioner's Opposition to Amended claims.
PO Reply to Opposition to Amended Claims: The PO files a reply to the Petitioner's opposition to amend the claims.
Period for Observations and Motions to Exclude Evidence: Motions may be filed by either party to exclude evidence, for example, to exclude deposition testimony (e.g., based on relevance or hearsay) or a motion to strike belated evidence. Generally, the PTAB waits until after the oral hearing, when it reviews the record in its entirety, to decide the merits of any motions to exclude.
Oral Hearing: An oral hearing may be requested by either party wherein each party is given an allotted amount of time (typically one hour) to present their case in person (witness testimony is typically not allowed).
Final Decision: the PTAB will enter a final written decision not more than one year from the date a trial is instituted. A party dissatisfied with the PTAB decision may file a request for rehearing, and/or a dissatisfied party may appeal the decision to the Court of Appeals for the Federal Circuit (CAFC).
The extent and cost of the above stages depend mainly on the size and resources available to the parties involved. For example, when both parties are smaller companies (or a non-practicing entity (NPE)), one or both parties may choose to forego using expert declarations which can significantly reduce or even eliminate the cost of discovery. Expert declarations typically provide little benefit, and so opting out of an expert declaration will reduce at least the consulting and deposition cost of that declarant (even if the other party opts to use an expert declaration). Most large law firms will recommend using expert declarations mainly because it increases their billing rather than provide any significant impact on the outcome of the PTAB decision. The PTAB board members are themselves experts in the field which is why they typically give little weight to paid "experts."