Continuing the Continuation-in-Part Discussion

I wrote about continuation-in-part applications earlier this week.  Consider this a continuation-in-part discussion.  I’m turning now to explore some of the reasons you may or may not want to file a CIP application.  And last week’s proviso remains: CIP application practice, is complicated and subject to many considerations about past disclosures and uses of the subject matter as well as future handling of the application.

The life of a patent used to be measured from the date the patent issued.  By filing a CIP application, you could potentially increase the protected lifespan of the inventive subject matter.  However, the law was changed so that patent protection now lasts for 20 years from the effective filing date.  Continuing applications adopt the filing date of the earlier-filed application, and thus likely lose a few of those 20 years during prosecution of the prior case.

Continuation-in-part applications include include two types of claims: those that include subject matter disclosed completely in the prior application, and those that include subject matter supported by the new disclosure.  The former claims receive the benefit of the earlier application’s filing date, while the latter claims get their own, new filing date.  This split in filing dates can create issues that may direct an inventor to file an original application instead.

If a CIP application is filed and the claims are supported by the old disclosure, then the CIP can be a very wise move.  It can help you avoid intervening prior art by giving your new application an earlier filing date.  However, the CIP application is filed and the claims aren’t supported by the old disclosure but only by the new disclosure, the CIP makes no sense; the earlier application’s filing date is not available, but the life of your CIP application will still be shortened.  These applications should probably be filed as original applications.  So, if there is new disclosure on which the claims are based, it generally makes more sense to file the claims in an original application rather than a continuation-in-part application.

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  1. I filed a patent application pro se over 2 years ago and the examination has just started. I am considering writing a CIP based on new research. My claims are very general because there is almost no prior art and the invention is about as simple as a wheel, which is a good analogy. If I described several forms of wheels in the specification but only used very generalized claims that covered all these different forms do you think it would be necessary to write a CIP so that the claims enumerated all the different forms? If you can comment on this I would appreciate it greatly.

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