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Intellectual Property: Post-Issuance & Interferences

Although patent reform in the United States is moving toward a first-to-file patent system, first-to-invent issues will still be relevant under grandfathering provisions in the America Invents Act. The remaining first-to-invent aspects of the U.S. patent system create the opportunity to effectively contest a patent outside the courtroom or even before a patent is granted. Such contests are carried out through the declaration of an interference proceeding by the U.S. Patent and Trademark Office, Patent Trial and Appeal Board ("Board"). Interference proceedings are unique to U.S. patent law. During these proceedings, the issues of who was first to make an invention and validity can be resolved.

The Board has jurisdiction to handle interference proceedings that involve two or more patent applications or those that involve a patent and one or more patent applications. In those rare situations where two interfering patents were granted by the U.S. Patent and Trademark Office, the only recourse for the parties is to address the issues of validity and priority in the U.S. courts.

LeClairRyan's patent interference attorneys possess a depth and breadth of experience protecting inventor's rights and ensuring they achieve maximum strategic advantages. Our team of interference practitioners has developed skills and experience in patent interferences involving a variety of technologies, including: 

  • Pharmaceutical compositions 
  • Vaccine components, including proteins and virus-like particles 
  • Diagnostic assays and platform technologies 
  • Microporous filter manufacturing 
  • Nucleic acid arrays 
  • Transgenic plants with pathogen derived resistance 
  • Replicase-mediated resistance in transgenic plants 
  • Pharmaceuticals 
  • Coaxial cable connectors 
  • Base coat/clear coat films 
  • Photographic technologies 
  • Manufacturing of thin film transistor of semiconductor devices

Following is a description of how the interference process is initiated and the two types of situations it involves, as well as how we ensure our clients are positioned for success during the process and how we can save our clients' time and money through alternative dispute resolution.

How Interferences are Provoked

Interference proceedings typically arise in two types of scenarios. The first occurs when interfering parties—and there may be more than two—were separately engaged in similar areas of research at roughly the same period in time. This usually results in an interference being declared between two or more patent applications, or an issued patent and one or more patent applications. The second scenario involves interfering parties that were engaged in a collaborative research program that became divisive, and each filed their own patent application(s) claiming common subject matter. These types of interference proceedings involve very different strategies, and we are well experienced in representing clients in both situations.

Interference proceedings can be declared by the Board on unsuspecting patent applicants, typically at the recommendation of the examiners handling the involved application(s). Alternatively, a party prosecuting a U.S. patent application can provoke an interference by demonstrating that (i) two applications (or a patent and one or more applications) owned by different parties claim the same or substantially the same subject matter; and (ii) the party seeking to provoke the interference has a basis for being awarded priority. We have experience in provoking interferences, and we also know how to work closely with our clients to quickly and thoroughly assess the extent of their priority case.

Two Phases of Interferences

For those unfamiliar with interference proceedings, be forewarned: It is litigation, and the timeline set by the Board moves fairly quickly. The proceeding involves two phases: a motion phase and a priority phase.

The motion phase is very important in trying to resolve the case without a priority phase and/or helping to improve an inventor's chance of prevailing in the priority phase. During the motion phase, the parties can file motions to accomplish the following: 

  • Gain benefit of the filing date of a prior application 
  • Prevent the opposing party from gaining such benefit 
  • Attack the opponent’s entitlement to a patent 
  • Change the subject matter of the interference 
  • Declare additional interferences (if they exist)

These motions are decided after the parties submit opening, opposition and reply briefs, typically supported by written testimony of expert witnesses and/or fact witnesses whose testimony is cross-examined through deposition.

In the priority phase, the parties present their positions on a number of factual inquires, including actual reduction to practice, conception, diligence, and, if applicable, derivation. This is also done through the submission of a brief supported by written testimony of expert and fact witnesses, as well as documentary evidence. The testimony of the witnesses is, as before, cross examined through depositions. Positions on priority are challenged in opposition briefs and rehabilitated in reply briefs, which are also often supported by declarations from expert and fact witnesses.

Interference Strategies

Interferences are time-consuming and expensive. For this reason, it is important to determine a strategy early in the process. By understanding the case and evidence, claims can be drafted to best position your cause from the beginning. For instance, it may be best to segregate non-interfering subject matter and interfering subject matter into two or more separate patent applications, which will allow the non-interfering subject matter to proceed to grant without being encumbered by the delay of an interference proceeding. Advance planning may prevent an interference proceeding altogether.

Furthermore, because the interference is conducted on a compressed schedule, it is important to gather documentation establishing invention dates and develop strategies based on that evidence before the interference is declared. Not only is such an approach helpful in litigating an interference, it is also helpful in settling one because the evidence that substantiates the dates of invention will be available early in the interference—when the parties are most likely to settle.

We have extensive experience in coordinating the gathering of invention date information and in prosecuting interfering patent applications to advantageously position our clients.

Alternative Dispute Resolution

Interferences can be fully resolved before the Board. However, to save time and money, interfering parties often wish to utilize alternative dispute resolution procedures, ranging from an exchange of proofs to binding arbitration to a truncated procedure before the Board. We have experience in formulating procedures that protect our clients' best interests and successfully handling interference proceedings utilizing a variety of alternative dispute resolution methods.


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