Patent Specification Drafting Considerations Highlighted By TF3 Limited V. TRE Milano, LLC

Is there any possible danger in using the abbreviation "i.e." in the specification of a U.S. patent application? The Federal Circuit's recent decision in TF3 Limited v. TRE Milano, LLC shows that the answer is "yes." The court provided a reminder that use of "i.e." in the specification signals an intent to define the term to which it refers. Thus, the court held that the term cannot be interpreted to be broader than the definition provided in the specification by the use of "i.e." when interpreting the term under the broadest reasonable interpretation standard before the U.S. Patent and Trademark Office.

More particularly, in this case the Federal Circuit reviewed a Patent Trial and Appeal Board (PTAB) decision in an inter partes review (IPR) of U.S. Patent No. 8,651,118 (the '118 Patent). Representative claim 1 of the '118 Patent reads, with emphasis added: