Why do patents often include method claims and apparatus claims?

When I send a draft patent application to an inventor who is new to the patent process, the inventor often asks why the claims seem to repeat themselves. A patent application often has one group of claims directed to a method, and another group directed to an apparatus or system. This can confuse new inventors because the two claim groups often appear to be very similar.

Why the duplication?  There are several reasons.

One reason is that method and apparatus claims can be directed to two separate groups of infringers. A patent gives its holder the exclusive right to make, use and sell the invention. Method and apparatus claims may each define the invention in a slightly different way. Some entities — such as a distributor or retailer — may sell an apparatus, but they will never practice a method of making or using the apparatus. Other entities (such as end users) may use the invention but not make or sell it. Depending on the situation, one set of the claims or the other could be more useful to assert against a particular infringer.

Another reason to include two groups of claims relates to the point in time at which damages start to accrue for infringing activity. Section 287 of the Patent Act limits recovery of damages for making/using/selling a patented article to the point in time where the infringer had actual notice of the patent, or constructive notice of the patent through marking. Because Section 287 refers to “articles” but not methods, courts have generally limited the notice requirement to apparatus claims, not system claims.

This interpretation by the courts dates back to at least 1936, when in Wine Railway Appliance Company v. Enterprise Railway Equipment Company, the Supreme Court said that Section 287 does not limit damages if the patent holder isn’t actually making articles to mark.

More recently, courts have clarified that if a patent is directed only to a method (i.e., there are no apparatus/article claims), Section 287 does not apply and notice is not required. (See Bandag, Inc. v. Gerrard Tire Co.) If a patent includes both apparatus and method claims, then Section 287 does not apply if only the method are asserted. (See, for example:  American Medical System Inc. v. Medical Engineering Corp., Crown Packaging Technology Inc. v. Rexam Beverage Can Co. and Hanson v. Alpine Valley Ski Area, Inc.) Whether or how Section 287 would apply if both types of claims are asserted has not yet been fully addressed by the Federal Circuit. (See Rembrandt Wirless Technologies, LP v. Samsung Electronics Co., Ltd.)

Because of this method/apparatus dichotomy, as well as the fact that Section 287’s notice requirement does not apply to an entity that holds — but does not practice – the patent, the notice requirement has been criticized as primarily benefitting non-practicing entities. However, so far Congress has not considered this issue to be worthy of an amendment to the Patent Act.

In addition, to avoid issues associated with the notice requirement some patent applicants may consider filing patent applications with only method claims or only apparatus claims. This may mean filing two applications on the same day, or filing a second application that claims priority to a first application. This adds to the expense, but it can help reduce the worry that insufficient marking will limit damages when asserting both method and apparatus claims.

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