Negative claim limitations will be interpreted just as broadly as positive claim limitations, which may significantly narrow the claim scope. Here, for example, method steps required to be performed “without the use of a vision guidance system” were found to exclude a variety of vision guidance systems, not just those of the type at the heart of the specification. It may therefore be best to ensure that negative limitations are crafted as narrowly as possible.
Background / Facts: The patent being asserted here is directed to the manufacturing of bedding components, including machines that automatically staple wire grids to wood frames to make mattress foundations (box springs). The asserted claims require certain method steps to be performed “without the use of a vision guidance system.”
Issue(s): Whether the claim language’s disclaimer of “a vision guidance system” only disclaims use of a particular type of “vision guidance system” described in the specification via reference to an older patent.
Holding(s): No. “Nothing in the claim language purports to restrict the term ‘vision guidance system’ to one particular system. Indeed, the claim uses the term generically, referring to ‘a’ vision guidance system—meaning one or more—rather than a specific system. … [A]lthough the [specification] uses the [older] patent in its preferred embodiments as a general point of reference, it does not express any manifest exclusion or restriction as it pertains specifically to the meaning of ‘vision guidance system.’ [] Nothing in the written description of the [specification] indicates that the claims should be read to refer only to the vision guidance system of the [older] patent. Indeed, the specification [] recognizes that there are different types of vision guidance systems and discusses two separate examples. … Given that the [specification] specifically uses the phrase ‘vision guidance system’ to refer to two different systems—that of the [older] patent and one that provides ‘less exact’ guidance—there is no indication that the patentee intended the claims to refer only to a system disclosed in the [older] patent.”