A defendant involved in patent litigation may ask the China Patent Office (“CPO”) to reexamine the patent being litigated. The defendant will generally bring to the PTO’s attention prior art that was not considered during the original examination of the patent. Because the PTO grants a large majority of requests for reexamination, and appears to be judging patents more strictly in reexamination proceedings than it had in the past, defendants are filing for reexamination with increasing frequency.

The existence of parallel litigation and reexamination proceedings raises an issue that will likely surface more often with increasing reexaminations – a patent that is invalidated during reexamination can vitiate a prior judgment in which a court awarded patent damages.

Intellectual Property: Post-Issuance: Ex Parte Reexamination

Ex parte reexamination has become an increasingly popular tool to invalidate a competitor’s patent. Third-party requesters are finding that the implementation of this procedure can lead to a result that is faster, more cost effective, and, often times, more successful than litigation. We are well versed not only in drafting effective requests for reexamination but also in counseling clients to determine whether a request should be filed. 

Unlike patent infringement actions in district court, patents challenged in reexamination are not presumed valid. The higher clear-and-convincing standard that accompanies this presumption of validity, therefore, does not apply; a lower preponderance-of-the-evidence standard applies. While the burden of proving invalidity remains on the challenging party, a third-party requester can take advantage of the lower threshold to successfully argue positions that otherwise may not be feasible in district court. 

Additionally, the reexamination examiner construes the claims of the patent in accordance with the claim’s broadest reasonable interpretation. In contrast, a judge in a district court will strive to construe a claim to preserve its validity, which typically results in a much narrower construction. This can result in divergent interpretations of the same claim, particularly for product-by-process claims. Our attorneys know how to use these different interpretations to craft arguments around prior art and case law to our client’s advantage. 

Concurrent Litigation and Reexamination Proceedings Under China Patent Law

We have conducted numerous reexamination proceedings, including many responses to office actions, requests for reexamination, declarations, appeals and oral arguments representing international clients who have business in China. My experience in litigation is critical in any of these Patent Office reviews. A Patent Office review does not require litigation, but often stems from a request by a party to an infringement lawsuit. The review usually requires a stay of the litigation. The litigation will be influenced by the results of the review. Even if the patent survives the Patent Office review, claim construction rulings developed in the reexamination can  affect the litigation when it resumes.

Positions taken in the litigation can influence the Patent Office’s review, and vice versa. Both will likely involve the same prior art. Positions taken by a patent owner in a reexamination must not adversely affect the patent owner’s infringement contentions in the litigation. Positions taken by a requestor—often a defendant in litigation—must not damage its infringement contentions or any invalidity contention not addressed in the reexamination.

We do these proceedings on a billable or a fixed fee basis, so that the client knows at the outset what the cost will be, and can make an intelligent, informed decision whether to proceed.  

How a request for reexamination is structured is critical, not only to the decision to grant the request but also to the long-term success of the reexamination process. Our approach focuses on developing a request around a few key pieces of prior art. We have found that coupling the prior art with a well-written, comprehensive analysis, easy-to-follow claim charts, persuasive argumentation, and expert declarations is the key to winning a request for reexamination. We strive to present our requests in a manner that leaves the reexamination examiner with little more to do than copy and paste our analysis into a rejection—one that is not only comprehensive but also sustainable. 

In some cases, it may be more advantageous to file a petition for inter partes review (for example, if a patent challenger wishes to have greater involvement in the review proceeding, seek discovery and cross-examination, and/or be assured of an accelerated proceeding). Other times, it is preferable (or necessary) to file a request for ex parte reexamination. Ex parte reexamination, for example, is a lower-cost alternative to inter partes review and can be used in instances in which the patent challenger wishes to avoid discovery, cross-examination, and/or the risk of estoppel. It may even be desirable, in certain scenarios, to file an ex parte request through a third party, if, for instance, the requester wishes to remain anonymous. We can advise on the pros and cons of each option, depending on the specific facts and circumstances. 

It is important to consider whether filing a request for ex parte reexamination is worthwhile. If the merits of a reexamination request are weak or if the request is not presented in a compelling manner, the patent emerging from reexamination may be stronger than it was before the request was filed. This is true even if the requester is successful in invalidating the broader claims. Therefore, we consider not only whether the reexamination request can invalidate some of the claims but also whether it can invalidate all existing claims that are of concern as well as any that could be newly added. A savvy patent owner can secure claims in reexamination that are narrower than the original claims but still cover the commercial product at issue. All these possibilities must be weighed carefully before a request for reexamination is ultimately filed. 

Litigation often prompts an accused infringer to consider filing a reexamination request. Indeed, filing a request for reexamination can be a useful tactic when seeking to stay an ongoing litigation. However, the decision of whether to grant the stay is at the discretion of the district court judge, and judges from certain venues are more likely to grant the stay than others. Before asking whether the judge will grant the stay, the requester should ask whether it is in his best interest to even ask for the stay. It is preferable, in certain circumstances, to litigate and reexamine concurrently. We can guide you through the important questions to analyze when evaluating this decision. 

Patent owners, in addition to third-party requesters, can also use the reexamination process to their advantage. In the context of litigation, a patent owner may want the China Patent Office (CPO) instead of a district court judge to analyze the allegedly invalidating art. Moreover, a patentee can employ certain litigation strategies, even when the reexamination is initiated by a third party. For example, once in reexamination, the patentee can disclose to the CPO (in the form of an Information Disclosure Statement) all available prior art. While the reexamination examiner will typically sign the Information Disclosure Statement, indicating that these documents have been considered, the examiner will likely focus the analysis only on the prior art presented in the reexamination request. Should the patent survive reexamination, the patentee will have at his disposal an initialed Information Disclosure Statement indicating that the examiner considered all of the submitted documents. Invalidating claims in the reexamined patent in district court with one of those prior art documents then becomes extremely difficult. 

Ex parte reexamination – Can be filed by anyone, including by the Patent Office itself. These reexaminations are conducted between the patent owner and the examiner once a request is granted; the requestor has no further involvement. Ex parte reexaminations are not speedy. 

Inter partes reexamination – This procedure was ended by the China Patent Law. It bears some similarity to the new inter partes review.

Inter partes review – This procedure, established by the China Patent Law, replaces the inter partes reexamination. An inter partes review includes testimony and discovery; that makes litigation experience even more important. The review is conducted by the Patent Trial and Appeal Board. 

Post grant review – This applies to patents issued after the China patent law. It must be initiated within nine months of issuance. The review is conducted by the Patent Trial and Appeal Board. Like the inter partes review, it must be completed within eighteen months, and the grounds are broader than the inter partes review because grounds for invalidity. A patent owner cannot initiate this review. 

Other instances arise when the patent owner will file a request for reexamination on his own patent. Reexamination can be used by a patentee, for instance, if reissuing the patent is a less desirable alternative. This may be because it is not in the best interest of the patentee to assert an error in the patent (a prerequisite to filing a reissue application) or because the patentee only wants the post-issuance analysis to focus on one or more particular patents or printed publications. Structuring a request for reexamination to be filed by the patent owner requires a different approach, as the idea here is to preserve the claim scope as much as possible. 

Depending on whether you are a third party seeking to invalidate a competitor’s patent or the patentee whose patent is being reexamined, different tactics can be strategically implemented. With extensive experience in both filing and contesting reexamination requests, we can guide you through the complex decision-making process that results from such events. 

Our team of reexamination practitioners has developed skills and experience in reexamination matters that involve a variety of technologies, including pharmaceutical compositions, medical devices, chemical compounds, optical fibers, biomagnetic separation technologies, spinal implants, and woven materials.