Practice by jurisdiction
The practice and procedure of filing a divisional patent application vary from jurisdiction to jurisdiction. In most countries, the filing of divisional applications is possible at least as long as the parent patent applications are pending. Since 2013, the European Patent Office rules are again in line with the current practice before the patent offices in the U.S., Germany, and Japan.European Patent Convention
Before the European Patent Office (EPO), divisional applications can be filed under . A European divisional application is a new application which is separate and independent from the parent application unless specific provisions in the European Patent Convention (EPC) require something different. : "The procedure concerning the divisional application is in principle independent from the procedure concerning the parent application and the divisional application is treated as a new application... Although there are some connections between the two procedures (e.g. concerning time limits), actions (or omissions) occurring in the procedure concerning the parent application after the filing of the divisional application should not influence the procedure concerning the latter...." The practice relating to the filing of divisional applications under the EPC was clarified by the Enlarged Board of Appeal of the EPO in June 2007. The Board held that a divisional application which on filing contained subject-matter extending beyond the content of the earlier application as filed could beUnited States
In the United States, a divisional application is seen as a type of continuing patent application, except that if a restriction requirement necessitated the filing of the divisional application, the law provides protection against a rejection of the application and against invalidation of thus-issued patent for double patenting.Cascade of divisionals
If a divisional application is filed based on a patent application that is already a divisional application, the newly filed divisional is a second-generation divisional, and so on, "thereby creating a cascade of divisionals".See also
*References
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