Incorporation by Reference – Friend or Foe?

Regardless of technology area or complexity of the subject matter, nearly all patent practitioners include the same phrase in every application they have ever written — “incorporated by reference herein.” Those magical words, according to the Manual of Patent Examining Procedure (MPEP), allow the referenced material to form “as much a part of the application as filed as if the text was repeated in the application.” [1]Incorporation by reference provides the patent drafter with the ability to reference, and include, information in an application without adding voluminous text to the specification. It serves the interest of the public by directing the reader to the required information, but removes the burden of wading through excessive text when describing an invention. But what happens when the reference is inconsistent with the application where it is being incorporated? A recent holding from the Federal Circuit in Finjan v. ESET [2]examines this scenario, and luckily for the patentee comes out on the side of the application drafter.

Finjan, Inc. filed suit against ESET LLC, asserting infringement of five patents. [3]At the Markman hearing at the District Court level, the court focused on the meaning of the claim term “Downloadable.” In two, non-asserted patents in the family, the term Downloadable was defined as “a small executable or interpretable application program which is downloaded from a source computer and run on a destination computer.” [4]Two of the asserted patents recited a definition of “Downloadable” that omitted the term “small,” but both also incorporated by reference the non-asserted patent definition that included “small.” [5]The three remaining asserted patents did not include a definition of “Downloadable,” but incorporated by reference one of the non-asserted patents as well as one of the asserted patents.

Faced with inconsistencies throughout the portfolio, the District Court construed the term “Downloadable” to mean “a small executable or interpretable application program which is downloaded from a source computer and run on a destination computer,” reasoning that the differences could be reconciled with this definition. [6]As a result of this claim construction, the court then found the asserted patents indefinite, based on insufficient description for the term “small.”

[7]On appeal, the Federal Circuit disagreed with the District Court’s handling of the term “Downloadable,” and specifically examined whether or not text from an incorporated reference, overrides the text into which it is incorporated.

While the Federal Circuit pointed out that definitions in incorporated patents or references do form part of the host patent, they “do[] not convert the invention of the incorporated patent into the invention of the host patent.” [8]Instead, the reader must look to the disclosure of the host patent to provide context to determine what impact, if any, incorporated text has on claim construction of the host patent. [9]Importantly, while these disclosures from related patents may certainly inform the construction of claim terms, the scope of a term does “not necessarily apply across patents.”

[10]Even though there are competing definitions within the family of patents owned by Finjan (both asserted and non-asserted), “the use of a restrictive term in an earlier application does not reinstate that term in a later patent that purposely deletes the term, even if the earlier patent is incorporated by reference.” [11]Because different terms can coexist in the patent family, a more narrow definition from an earlier patent, even though incorporated by reference, need not control. [12]Based on this conclusion, the Federal Circuit reversed the District Court’s claim construction, and vacated the finding of invalidity for indefiniteness.

[13]Certainly, for patent practitioners, the decision in Finjan provides a welcome confirmation that it is the text of the current specification that ultimately controls how a claim term will be interpreted, not how a prior application may have used the term. [14]Thus, while prosecutors should not fear using the time- and verbiage-saving tool of “incorporation by reference,” it is important to remember to make sure that the context in which it is used is carefully considered.

[1] See M.P.E.P. § 2163.07(b).
[2] Finjan LLC v. ESEL, LLC, 2021-2093, Fed. Cir., Nov. 1, 2022.
[3] Id. at page 2.
[4] Id at page 4 (emphasis in original).
[5] Id.
[6] Id. at page 5.
[7] Id.
[8] Id. at page 7, citing X2Y Attenuators, LLC v. U.S. Int’l Trade Comm’n, 757 F.3d 1358, 1362-1363 (Fed. Cir. 2014).
[9] Id. at page 7.
[10] Id., citing X2Y at 1366.
[11] Id. at page 8.
[12] Id.
[13] Id. at page 10.
[14] With review of the prosecution history, when required under Philips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005).