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Conclusion

Accordingly, although "it is the claims that measure the invention,"20 the entire patent application, including the claims, specification, and drawings, must be carefully examined by a patent applicant before submitting the application and statements made to the patent examiner scrutinized before submitting responses. Embodiments described in the specification and arguments made to the Patent and Trademark Office should avoid using the phrases "the invention" or the "present invention" and should, instead, describe embodiments as alternatives, e.g. the "preferred embodiment" or "as claimed in claim 'x.' "21 When responding to an office action, patent applicants should clearly narrow their argument to address just the claim being discussed and avoid any argument that includes the phrases "the present invention" or "the invention" unless those phrases are specifically narrowed to the claim being distinguished.

Additionally, patent litigators should examine the entire file history for these statements during their Markman exercises. When litigating, the parties (defendants, especially) should review the specification and file history for instances of use of the phrases "present invention" or "the invention" for further analysis of limitation of claim scope.