Not on purpose, mind you. But the Federal Circuit in Columbia University v. Symantec Corp urges mindfulness with regard to the often perfunctory practice of incorporating by reference the contents of a provisional application into a non-provisional application that claims the benefit thereof. While the applicant should in the majority of situations expressly incorporate the content of a provisional in its entirety, selective inclusion of subject matter into a non-provisional may be preferable where an incorporated definition for a claim term could be used as evidence that a claim is indefinite.
In Columbia Univ., the Federal Circuit affirmed a lower-court holding of claim indefiniteness in one of the asserted patents, U.S. Patent No. 7,487,544 (“the ’544 patent”), in part by relying on evidence from an incorporated provisional application that narrowly defined the disputed claim term “byte sequence feature.” The provisional application, which was a research paper by the inventors of the ‘544 patent, stated that “[t]he byte sequence feature is the most informative because it represents the machine code in an executable instead of resource information….”
Based in part on this evidence from the provisional application and the text of the ‘544 patent written description, the court narrowly defined the disputed claim term, “byte sequence feature,” as representing machine code instructions. Because a step in the claims of the ‘544 patent that referenced the “byte sequence feature” was clear only according to a broader definition that did not include this requirement, the Court determined the step was “nonsensical” and held the claims indefinite:
Claims 1 and 16 conflate a “byte sequence feature,” which is a feature extracted from machine code instructions, with the extraction of “resource information,” which is not a machine code instruction. Specifically, the claims describe the step of extracting machine code instructions from something that does not have machine code instructions. (“extracting said byte sequence features from said executable attachment comprises creating a byte string representative of resources.”) (emphasis added). The claims are nonsensical in the way a claim to extracting orange juice from apples would be, and are thus indefinite.
The court therefore arrived at the indefiniteness holding by drawing evidence from what is, at first blush, a latent ambiguity in the ’544 patent, i.e., an ambiguity that “arises from extraneous or collateral facts which make the meaning of a written [instrument] uncertain although the language thereof, on its face, appears clear and unambiguous.” However, citing the long-standing legal rule that material properly incorporated into a document by reference is “effectively part of the host document as if it were explicitly contained therein,” the court drew no distinction between the language of the ‘544 patent description and that of the incorporated provisional application. Any ambiguity resulting from competing descriptions of a patent’s text and material incorporated by reference into the patent instrument is an ambiguity in the specification as a whole. Because the specification is accorded the most significant weight under the authoritative Phillips framework for claim construction, courts can readily use such internal ambiguities to find a disputed claim term indefinite where the term is implicated.
The danger to the applicant is that the subject matter of an incorporated provisional application does not appear within the primary text of the non-provisional application. Despite the equivalent weight accorded to the written description and incorporated material, the applicant may be tempted for various reasons to discount or to even neglect the content of the incorporated material during prosecution. For example:
- Whereas the written description is typically written by a patent practitioner, the incorporated material may have been written by the inventors or another party that has little or no experience drafting patent applications.
- Relatedly, the purpose in drafting the incorporated material may have been unrelated to patenting.
- Incorporated material may be voluminous and mostly tangential to the claims of a pending application but incorporated in its entirety for reasons of completeness or convenience.
- Incorporated material may be awkwardly formatted, hand-written, or otherwise difficult to understand.
- Incorporated material is typically located in a separate file than that of a pending application.
- The text and figures of an incorporated provisional application are often wholly-reproduced within the primary text of a non-provisional application, i.e., not by incorporation, which may lead the applicant to assume, incorrectly in some cases, that the patent application mirrors the incorporated material.
- An incorporated provisional may have been drafted quickly to meet a pending bar date and not be reflective of a current, more thorough understanding on the part of the practitioner.
Columbia Univ. is a reminder to applicants that any temptation to weight the primary text of a pending application more highly than material incorporated therein should be resisted. Moreover, the above analysis applies not only to patent applications incorporated by reference but also to non-patent literature. It is well-known that in order to ensure that all description necessary to fulfill the requirements of 35 U.S.C. § 112 is available to the public or to the U.S. Patent & Trademark Office (PTO) at the time of filing, 35 U.S.C. § 1.57(d) only permits essential matter to be incorporated by way of reference to “a U.S. patent or U.S. patent application publication, which patent or patent application publication does not itself incorporate such essential material by reference.” However, non-patent literature is part of the specification if properly incorporated by reference, and in spite of the distinction between U.S. patents / publications and non-patent literature with respect to essential matter, there is nothing to prevent a court from relying on a contradictory description found in non-patent literature as evidence to narrowly interpret or even invalidate a patent’s claims.
Whatever benefits are to be obtained from incorporation by reference, whether convenience, “economy, amplification, or clarity of exposition,” these are of course outweighed by the risk of invalidity. Columbia Univ. demonstrates that incorporated subject matter can be harmful as well as helpful to producing valid claims. Applicants should be mindful when considering incorporated (or whether to incorporate) subject matter at various stages of the process in order to ensure that issued claims are definite.
For example, to provide support for broad initial claim scope and flexibility in amendments, applicants should assign a similar level of care to the preparation of provisional applications as to non-provisional applications. The court in Columbia Univ. noted that descriptions of the disputed claim term in the specification and incorporated provisional application “are not simply descriptions of the preferred embodiment but are statements defining ‘byte sequence feature.’” Accordingly, subject matter should wherever possible be described in terms of examples and embodiments to provide support for varying amounts of scope for claim term definitions that can fit comfortably within a future preferred construction. When possible, applicants may wish to avoid filing research papers, specifications, articles, and other inventor-drafted material as-is and instead insert the language of ‘embodiment’ or ‘example’ while modifying definitions that are unnecessarily limiting.
Care should also be taken during application preparation when the decision whether to incorporate material by reference is being made. It is possible and even likely that the patentee in Columbia Univ. was aware, as of the application filing date, that the provisional application included a limiting description for “byte sequence feature.” Although the provisional application defined the term as representing “the machine code in an executable instead of resource information,” the primary text of the ‘544 patent merely stated “that the ‘byte sequence feature’ is useful and informative ‘because it represents the machine code in an executable.’” The patentee actually removed the explicit disclaimer to “resource information,” used by the court as evidence of indefiniteness, from the primary text of the non-provisional application. The disclaimer was nevertheless included in the specification of the ‘544 patent as issued because the provisional was incorporated by reference in its entirety. Where a provisional application or other material being considered for incorporation includes subject matter that could render the claims indefinite, applicants should consider excluding such subject matter either by selective incorporation (rather than in the entirety) or by including the material in the primary text sans any limiting or otherwise harmful description. Even so, far better at the outset to preserve the convenience offered by incorporation in the entirety—an ounce of care during the preparation of a provisional application is worth a pound of revision down the line.
Of course, in the majority of cases, incorporating a provisional application into a non-provisional application by reference in its entirety remains warranted. The court in Columbia Univ., however, counsels applicants to avoiding inadvertently incorporating indefiniteness by preparing provisional applications with care and conducting prosecution with due regard for incorporated subject matter, thereby ensuring that the “fully-integrated written instrument” that is a U.S. patent does not mandate unintended claim term definitions that makes its claims unclear and invalid.
 Trustees of Columbia University v. Symantec Corp., No. 15-1146, slip op. (Fed. Cir. 2016).
 By meeting the requirements of 37 C.F.R. § 1.57(c). 37 C.F.R. § 1.57(b) offers a constructive form of incorporation by reference, but this constructive incorporation is only effective as to subject matter that is “inadvertently omitted from an application” (emphasis added).
 “[T]he intended definition of this term does not include information other than machine code instructions.” Columbia Univ., slip op. at 11. The narrow definition of “byte sequence feature” also led to a holding of non-infringement of the ‘544 patent by the accused Symantec products.
 Columbia Univ., slip op. at 12–13 (internal citations omitted).
 Duquesne Light Co. v. Westinghouse Elec. Corp., 66 F.3d 604, 614 (3d Cir. 1995). Although the court cited other evidence from ‘544 patent supporting its narrow interpretation of “byte sequence feature,” the evidence from the incorporated provisional application was the most significant to the indefiniteness holding because it specifically excluded “resource information” as being representative of a “byte sequence feature.” This exclusionary language does not appear in the primary text of ‘544 patent.
 Columbia University, slip op. at 10 (citing Advanced Display Sys., Inc. v. Kent State Univ., 212 F.3d 1272, 1282 (Fed. Cir. 2000)).
 Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005).
 Columbia Univ., slip op. at 11–12 (“The patentee cannot rely on its own use of inconsistent and confusing language in the specification to support a broad claim construction which is otherwise foreclosed.”).
 I refer to “primary text” of an application to mean text that is not incorporated by reference.
 See Application of Hawkins, 486 F. 2d 569, 574 (CCPA 1973).
 37 C.F.R. § 1.57(d).
 See 37 C.F.R. § 1.57(e) (“Other material (‘Nonessential material’) may be incorporated by reference to … non-patent publications.”) (emphasis added).
 Application of de Seversky, 474 F. 2d 671 – Court of Customs and Patent Appeals 1973.
 Columbia Univ., slip op. at 10.
 Columbia Univ., slip op. at 10 (quoting ’544 patent, col. 6 ll. 12–14).
 See also X2Y Attenuators, LLC v. ITC, 757 F.3d 1358, 1363 (Fed. Cir. 2014) (“[T]he disclaimers of the incorporated patents are a part of the asserted patents.”).
 Phillips at 1315.