The doctrine of claim differentiation does not apply where the claims are not otherwise identical in scope. Here, for example, while certain claims clearly distinguished between “instances” of text strings and “all instances” of the text strings, the claimed invention was found to be limited to linking all instances in view of the specification and because the differentiated claims were all independent claims with otherwise varying scope. “[W]e have declined to apply the doctrine of claim differentiation where, as here, the claims are not otherwise identical in scope.” It may therefore be helpful when trying to broaden a claim term to add different dependent claims directed exclusively to the different embodiments desired.
Background / Facts: The patent being asserted here is directed to the insertion of automatically generated hyperlinks for text strings found in various files. This allows instances of certain text strings to be linked to different sites or files for each user. Among the claims, claims 2 and 9 recite linking “instances” of text strings in selected files while claims 14 and 15 recite generating links between “all instances” of a link term in the selected files.
Issue(s): Whether claim differentiation precludes a construction of the link claim terms as requiring all instances to be linked, rather than a subset, because certain claims recite linking instances while other claims recite linking all instances of the link terms.
Holding(s): No. “Importantly, … all of claims 2, 9, 14, and 15 are independent claims, and we have declined to apply the doctrine of claim differentiation where, as here, the claims are not otherwise identical in scope. [] Further, ‘[a]lthough claim differentiation is a useful analytic tool, it cannot enlarge the meaning of a claim beyond that which is supported by the patent documents, or relieve any claim of limitations imposed by the prosecution history.’”