A divisional patent application is a specific type of utility patent application. According to the United States Patent and Trademark Office (USPTO), you are only allowed one invention per patent. If an examiner determines that there is more than one invention within the scope of your patent claims, you will be asked to select which invention you’d like to proceed with for your first non-provisional patent application. The other creations or inventions can be filed separately as divisional patent applications.
Simply put, divisional patent applications must contain subject matter from a previously filed application, which is often referred to as the “parent application.”
According to the USPTO’s Manual of Patent Examining Procedure (MPEP), “unity of invention” is required in a patent application. This means that each patent application must focus on one invention or "a group of inventions so linked as to form a single general inventive concept.” If the patent examiner determines that the application does not have unity of invention, the patent will be rejected and the applicant will be asked to submit divisional applications for each single inventive concept from the original “parent” patent.
Although the wording does not need to be identical, divisional patent applications need to include subject matter that was initially disclosed in the parent application. Divisional applications cannot introduce new information about the invention.
It is also important to keep in mind that the divisional patent application adopts the parent’s filing date, which can play a role in a variety of factors, including the patent’s lifespan. Further, since US patents operate on a "first to file" system, it is especially beneficial to claim an earlier filing date.
Similar to divisional patent applications, continuation patent applications are filed following a previous parent application. The continuation application typically seeks to obtain broader patent protection or submit claims directed to a competitor.
In other words, divisional patent applications cover different patents within a single invention, whereas continuation patent applications modify the claims of the same patent.
To summarize, a divisional application typically has the same description as the parent application, but with a different set of claims. Divisional patent applications are an incredibly helpful resource for those who wish to modify their original patent application while maintaining their original filing date. However, with their strict requirements and extensive paperwork, patent applications can be complicated and intimidating. If you're interested in applying for a patent, one of our intellectual property attorneys can lead you through the process.