Terms and Concepts

Claim Construction

The standards for claim construction are very different in district court litigation as compared to patent reexamination proceedings.  During reexamination proceedings, claims are construed with their broadest reasonable interpretation, consistent with the specification [In re Yamamoto, 740 F.2d 1596, 1571 (Fed. Cir. 1984)].  For this reason, a Markman order in district court has no preclusive effect on the PTO and is not binding thereon [In re Trans Texas Holdings Corp., 498 F.3d 1290, 1297 (Fed. Cir. 2007)].  A broad claim construction draws in more potential prior art.

When a patent owner loses their ability to amend the claims (e.g., when a patent term expires during the reexamination proceeding), the standard for claim construction moves from the broadest reasonable interpretation standard to a standard “pursuant to the principle set forth by the court in Phillips v. AWH Corp., 415 F.3d 1303, 1316, 75 USPQ2d 1321, 1329 (Fed. Cir. 2005)(words of a claim ‘are generally given their ordinary and customary meaning’ as understood by a person of ordinary skill in the art in question at the time of the invention)” [MPEP §2258.I.G]. 

In U.S. district courts, on the other hand, claims are often construed so that they remain valid in view of prior art.  The court looks to get the “correct” claim construction after reviewing the parties’ respective positions. Such a construction will typically be narrower than that used by the PTO and may thus limit the world of available prior art.  This is not a merely academic distinction—the difference in claim construction can have real world effects in the parallel universe.

Consider a situation where a court issues a claim construction order in a litigation and the patent owner is ultimately successful in defending its intellectual property right against an invalidity challenge based on this claim construction.  The defendant (or another third party) may subsequently challenge the patentability of the same patent in the PTO.  In this situation, the PTO, using a broader construction, creates a different scope for the claims, and arguably a different intellectual property right.  In such cases, the patent owner is not permitted to adopt the claim construction of the court.  Due to these different claim construction standards, a patent owner may be forced into the difficult circumstance of having to amend claims to incorporate the court’s construction and potentially lose past damages, or continue to argue the issue in the reexamination proceeding and potentially extinguish all intellectual property rights in the patent. 

It is technically true that patent owners have the ability to amend claims during reexamination, provided the amendments do not enlarge the scope of the claims.  In parallel universe situations, however, this ability is severely circumscribed. 

First, substantive amendment of asserted claims could literally wipe out a district court or ITC Markman ruling.  If the litigation or ITC investigation has progressed to trial, substantive amendment of asserted claims could result in an enormous waste of judicial and party resources—sometimes to the tune of tens of millions of dollars.  Second, if a patent owner is forced to amend claims to preserve patentability, it risks the loss of any claim to past damages under the intervening rights doctrine, which is fully applicable to reexamination proceedings [35 U.S.C. §§ 307(b) and 316(b)].  In many instances, this not an insignificant prospect.  Third, in inter partes proceedings, the patent owner is not allowed to interview the examiner.  If the patent owner decides to first argue around the prior art and then is faced with a final Office action, there is little room for the type of negotiation necessary to arrive with claim amendments likely to be successful in overcoming pending final rejections.  Thus, in reality, patent owners have an extremely limited ability to amend claims.


  • Broadest Reasonable Interpretation
  • Markman Order in District Court