Archive for the “Continuations” Category

It may seem obvious in hindsight, but a regular utility application is a continuation or CIP of any earlier filed provisional application. If you add material to the provisional, as most often is the case, then any claims directed to that new material do not get the priority date of the provisional. See Finnegan’s blog post: Getting Priorities Straight: Patents Have No Presumptive Entitlement to Priority Date of Provisional Applications

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We all know about the duty of candor – the requirement that we inform the examiner of any possibly pertinent material – but how many of us realize we effectively have a duty to wave red flags for the examiner when we broaden a claim during examination.

Mr. Nouri Hakim thought he had a pretty good infringement case against Cannon Avent Group. His patent covered a leak resistant drinking cup that has a suction actuated valve that passes fluids when a person sucks on the spout but that is sealed when no suction is applied.

Cannon’s leak resistant drinking cup sure matched up to the claims in Hakim’s patent, US6,321,931 – at least it seemed to until Cannon’s attorneys read the “file wrapper”. The ‘931 patent was based on a continuation application that broadened the claims of the original, “parent” application. And Cannon identified a subtle but important limitation to the scope of the ‘931 patent buried in the negotiations between Hakim and the PTO during the prosecution of the parent application.

During the original prosecution Hakim responded to an office action by arguing that none of the prior art references included “a no-spill mechanism having a slit sitting against a blocking element such as is recited in all of the pending claims” (emphasis added). The examiner agreed and allowed all the claims.

After receiving the notice of allowance Hakim filed his continuation application and amended (and apparently broadened) the claims by changing “slit” to the more general “opening”. An accompanying letter stated that the claims were being broadened. The examiner allowed the new claims without further comment.

Getting back to the infringement suit, Cannon’s attorney’s successfully argued to the district court and the CAFC that simply informing the patent examiner that the new claim term (“opening” instead of “slit”) was broadening was not equivalent to rescinding the disclaimer that separated the invention from the prior art references.

While everyone agrees that a continuation application can be used to recapture claim scope given up during the original prosecution, the CAFC  said “…the prosecution history must be sufficiently clear to inform the examiner that the previous disclaimer, and the prior art that it was made to avoid, may need to be re-visited“. Thus it is not enough to say “I’m broadening my claims”; you must also say, “I want to change my argument about why the broader claims should still be allowed in spite of the prior art”.

In effect, you must take the responsibility for pointing out to the examiner how your changes relate to the previous actions; the “default assumption” is that any argument you made earlier is still in effect during the continuation prosecution. After all, “continuation” means still part of what went before.

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