In claim drafting, like the song says, “little things mean a lot.” (Mikkelsen Graphic Engineering Inc. v. Zund America, Inc.)

As anyone who has read our informative yet witty book, Essentials Of Intellectual Property, should be aware, broad patent claims are good. However, claims which are too broad are not good. (MagSil Corp. et al. v. Seagate Technology, et al.)

As the reader may (should) remember, an article claim of a patent is infringed if all of the claim limitations are found in the accused product. Note that this statement is silent as to when the claim limitations must be present. A recent case turns on that fascinating – to patent attorneys – issue. Gemtron Corporation v. Saint-Gobain Corporation

As the reader may (should) remember, basically there are two kinds of patent claims: article claims¹ and method or process claims. Article claims are comprised of multiple article limitations, and method claims are comprised of multiple steps or process limitations. Both types of limitations are fine but, just as we are abjured to mix milk and meat, so too we are directed – albeit by a different authority – not to mix article limitations and process steps in a single patent claim. Rembrandt Data Technologies, LP v. AOL LLC et al.

Broadly speaking¹, patent claims may cover either products (article claims) or processes (method claims). Method claims have become increasingly common as inventors seek to patent various methods of conducting business operations, especially conducting business via the internet – the infamous “business method patents.” Infringement of a method claim occurs when each step recited in the claim is performed in the practice of the accused process. Moreover – and an aspect frequently overlooked by both patentees and patent draftspeople,² each step must be performed by the same party.