Some inventors are lucky enough to be able to focus on inventing in a single field or technology area. Often, they generate lots of inventions that are related in some way. In the recent past, when the fees that the UPTO charges for examining related inventions were lower, it almost always made sense to cram as many simultaneously-invented inventions as possible into a single patent application and then attempt to entangle the inventions using linking claims (see my ”how to” article) to force the examination of as many claims as possible in each patent application. That usually resulted in lower overall costs over the lifetime of the patent. Now, other options must be considered.
If a patent application discloses and claims inventions that are deemed “independent and distinct” by the Examiner, the Examiner will place the claimed inventions in groups and require that the inventor elect a single group to be examined for the single filing fee paid by the inventor.
In some situations, it makes sense for the inventor select a particular group (e.g., one of his claimed methods), add some claims to the case to both link the elected group to another group (e.g., a product made in accordance with the method) and add some claims to the product itself. That approach can get expensive these days because the USPTO currently (2009) charges $110 for each independent claim over 3 and $26 for each independent and dependent claim over a total of 20 in each application. If one of the inventions is likely to be more valuable or is likely to be infringed first, it often makes sense to elect it for examination first. If all of the inventions are likely to have value, it often makes sense to elect a “method of making” group and then link the product to it as explained above.
If lots of claims (more than 3 independent claims and 20 total claims) are going to be needed to adequately protect an elected group, it can make sense to file divisional applications on each group, because the small entity filing, search and examination fee (3 independent claims and 20 total claims) is $545 these days (2009). Each divisional application can contain claims only to a single group that was identified by the Examiner. If claims are made to “independent and distinct” inventions in other groups or in none of the groups, then the Examiner will again require that the inventor select one of the identified groups. If the claims in the original application were well written and the grouping by the Examiner makes sense (in that each group clearly identifies an invention that is separately patentable), filing a “divisional” application has the advantage that the claims to the separately patentable invention cannot be rejected on the grounds of double patenting. Furthermore, no prior art that arises after the filing date of the original application can be used to reject claims in the divisional that were adequately supported in the original application.
If an inventor wants to claim an invention an invention that was disclosed in an original patent application (or in a subsequent patent application that is filed by the same inventor or inventors during the pendency of the original patent application or during the pendency of a subsequent patent application in a chain of such applications), then a “continuing” application must be filed containing claims to the invention. If new disclosure is introduced into the application, then the application must be filed as a “continuation-in- part (CIP)” application. Prior art that arises before the filing date of a CIP application can be used to reject claims to any inventions that are first adequately disclosed in the CIP application. A pending grandparent or parent, etc. patent application (if it has not been published more than a year before you file your CIP) cannot be relied upon by the USPTO to render your improved invention unpatentable. (See my “how to” article for details.) The 20-year term of a divisional, continuing or CIP application begins on the filing date of the first nonprovisional patent application in the chain, so there is a practical limit to the number of applications that can occur in any one chain, especially as average pendencies are increasing to 3, 4 and 5 years.
In order for a chain of priority applications to be created, each subsequent application must be filed before the abandonment, patenting or termination of court proceedings (if any) of at least one earlier-filed application in the chain. Moreover, a priority claim to all the earlier-filed applications in the chain must be present in each application as filed or added to each application within the later of 16 months after the filing date of the prior application in the chain or 4 months of the filing date of the later application. If such a claim is not made in time and the error is unintentional, a petition and fee (currently $1,410 in 2009) can be filed and the USPTO will accept the delayed priority claim (but the petition must be filed during the pendency of the application in which the error was made).
Each a subsequently-filed application must also meet the three criteria for adequacy of disclosure of a patent application on the day it is filed: written description, enablement and best mode (although best mode information need not be updated in later-filed continuing applications). If the subsequently-filed application does not contain (within its specification, drawings and claims) sufficient disclosure to meet all of these criteria for all of the inventions the inventor wants to eventually claim, it must incorporate by reference the disclosure of the previously-filed applications (or patents) in the chain that do. The incorporation by reference statement must appear in each application as filed and cannot be added later, but breaks in the disclosure chain are allowed. (An incorporation by reference statement added after an application’s filing date is not effective because no new matter can be added to an application after its filing date.) Incorporation by reference of disclosure from documents other than earlier patent applications or patents filed by the same inventor(s) must meet stringent rules.
In summary, in order to “keep your foot in the door of the USPTO,” that is, be able to claim an invention disclosed in a previous patent application in a subsequent patent application by the same inventor(s), AND in order to be protected from prior art that has arisen after the filing date of that previous application (called the “critical date”), both a priority claim must be made in the subsequent application as filed (which if unintentionally delayed can be added later) AND the subsequent application must either adequately disclose the claimed subject matter or must, as filed, contain an incorporation by reference statement to (1) a U.S. patent, (2) a U.S. patent application publication, or (3) a pending U.S. application that does adequately disclose the invention. Furthermore, abandoned applications less than 20 years old can be incorporated by reference (at the time of filing) to the same extent as copending applications, because both types are open to the public when the referencing application issues as a patent.
If an invention is not anticipated by or obvious in view of a patent or published patent application (including the inventor’s) (or any other prior art), then it can make sense to file an original patent application on that invention. This will safeguard the 20 year term of the patent in that the term will begin on the filing date of the nonprovisional application and the beginning of the term can be effectively delayed from beginning for up to 12 months by filing a provisional application first.
Why are all these patent applications necessary? Because U.S. patent law only allows one invention to be claimed in each issued patent. A claim to an entire assembly does not protect a subassembly. A claim to a method does not protect a single step in that method. Only if a person performs every step of a patented method or makes a structure containing all the elements of a patented structure is that person infringing a patent. Alternatively, if someone induces infringement by selling a product that can be used only to practice a patented invention, that person is contributing to infringement and the patent owner can enforce his or her patent by suing the person for patent infringement (suits that can cost each side $1+ million these days, by the way). So, patenting lots of separate inventions requires that lots of patent applications be filed and prosecuted.
If many valuable inventions have been invented, it is easy to see that the filing and prosecution of many patent applications (not to mention the enforcement of the issued patents) can exhaust not only the financial resources but the sanity of an inventor. Unfortunately, that is how the game is played. The key is to file patent applications only on valuable inventions. I explain how to value your invention on my website.