Sufficiency of disclosure and the great divide between the U.S. and Europe


The United States patent system has undergone significant change within the last few years. In particular, it has transitioned from a first to invent system to a first to file system. Some commentators have suggested that such change is an attempt to further “harmonize” the U.S. patent system with other patent systems of the world, such as the one in Europe.

However, a close analysis of the disparate disclosure requirements in the United States and Europe demonstrates that such harmonization is incomplete. Indeed, a number of patent practitioners regularly must plan for and address the significant “sufficiency of disclosure” differences that exist between these two systems when drafting and prosecuting patent applications, and enforcing patents. This is especially problematic for patent families in which such cases are prosecuted in the United States and Europe with the same or similar specification and claims.

The United States is a two-step process: one step focusing upon what is actually invented (i.e., “written description”) and the other focusing upon what has been enabled for a person skilled in the art (i.e., “enablement”). In other words, to illustrate written description, the patent applicant/inventor must clearly describe what the inventive technology is, how to utilize and make the invention, and what the advantageous outcomes of the invention are. The goal is that a person of ordinary skill in the art can precisely understand and reproduce (without undue experimentation) what the inventor has claimed as his/her invention.

Europe employs a one-step approach focusing upon enablement and does not employ a separate written description requirement. Although some comments have suggested that Article 84 EPC may provide for a “written description” requirement in Europe, such a proposition does not hold true. Article 83 EPC does focus upon an enabling disclosure. Article 84 EPC, on the other hand, really appears to be focused upon proper claiming. For example, one of the Technical Boards of Appeal of the European Patent Office in Technical Decision T0939/92 determined, “[T]he expression support by the description ‘means that the technical feature stated in the description as being an essential feature of the described invention must be the same as those used to define the invention in the claim . . . ” This particular decision appears to illustrate that Article 84 EPC is more akin to the United States’ antecedent basis requirement of 35 U.S.C. § 112, paragraph 2, with respect to proper claim drafting.

Thus, the European approach requires that the inventor fully disclose the problem to be solved and the technical solution to that problem (via the invention). Such an approach favors an expansive disclosure with at least one very detailed embodiment. Further, a number of comparatives against the prior art are typically provided and a discussion of the solution(s) that the invention provides to the problem(s) unresolved in the prior art. Claims are then provided that very distinctly track the words (and typically only those words) from the literal description, itself.

In the United States, an expansive disclosure is also provided, especially in light of recent case law. However, typically in the United States a disclosure of the problem to be solved is not required. Indeed, a “background of the invention” section is not required within a U.S. patent application. This is typically done because many U.S. practitioners do not wish to provide a “comparative roadmap” of the claimed invention and prior art which an examiner could potentially utilize when applying a flexible obviousness analysis via the KSR decision. Further, U.S. practitioners will also include a number of expansive paragraphs and terms illustrating a variety of differing alternatives or aspects of the invention’s various embodiments. However, many times, the actual examples provided do not provide the same level of breadth as the written word descriptive sections attempting to broaden the claimed invention. To overcome this, a number of prophetic examples are sometimes included in the specification, especially in the chemical arts. This practice is preferred in the United States to potentially broaden claims, provide a supportive point(s) for continuation practice, or set forth a defensive publication against potential competitors. Finally, many U.S. practitioners will utilize incorporation by reference to draft more efficiently and per preferred USPTO practice.

European practice, on the other hand, does not allow for the use of expansive terms like “about” because a definitive “metes and bounds” to a claim cannot be ascertained. Further, European practice does not allow for the use of incorporation by reference to information from another patent application. Europe’s patent application style embodies a “show me page, show me line” type approach. Finally, actual examples with supportive results are preferred, if not inherently required, in Europe. Prophetic examples can be included, but are typically viewed with a negative eye by European examiners.

Because the drafting goals differ greatly, many U.S. and European practitioners are faced with difficult decisions when attempting to draft a “global” or “harmonized” parent patent application (either as a national application or a Patent Cooperation Treaty (PCT) application). To these commentators, the solution to such issues may be to consider the development of both systems over time, then utilize different drafting styles. Clearly, both the United States and Europe favor disclosure, preferably expansive and fully supportive disclosure. As a result, there are a few different description and claim drafting options to consider.

  1. Draft the specification with a European approach (expansive but without the inclusion of omnibus paragraphs and terms (e.g., the word, “about”) but draft permutated claims in both the United States (include the word about) and European styles. In doing so, the more restrictive European requirements have been met, yet claims could be presented to the respective patent offices. Further, that description could be utilized on a global basis via the PCT process as well. The U.S. practitioner, for example, could also consider during prosecution deleting the “background of the invention” section via the amendment process. However, this could be viewed as a disavowal or a negative admission. An alternative may be to utilize a substitute specification. Or finally, modify the European-style application before initial filing to recast the problem to be solved as a number of advantages to be achieved. Many European practitioners do this today when presented with a U.S. national application for conversion into a subsequent European patent application or national application in a European country.
  1. Draft the specification as a European-style application (see No. 1 above) but again include both U.S. and European-based claims. However, this application will be filed as a PCT application outright. Then, during the PCT process, consider amending the specification to the desired style (U.S. or EP) via the Article 34 or Article 60 amendments. Additionally, at the time of national-stage or regional-phase entry consider presenting only the desired claim set(s) (U.S. or European) for purposes of patentability examination. It should also be considered that both claim sets could be moved in either system and then merely address unity, restriction and claim format objections as needed when presented by the respective patent office.

Either approach presented above allows patent practitioners to consider the advantages and disadvantages of each to be potentially implemented for the specific patent application/disclosure presented. However, neither approach is an absolute, and commentators appreciate that other approaches are also potentially available depending upon, for example, client desires/familiarities with their patent portfolios, practice preferences, and cost, among others.

The United States and European systems have attempted to become more harmonized with respect to a sufficient disclosure, especially in light of the United States’ recent America Invents Act. However, a perfect balance has not been struck. Patent practitioners must still carefully consider the particular patent application to be drafted and where it may be filed (i.e., nationally, regionally or globally). This article is an attempt to sheds some light upon potential solutions to create a patent application that is impervious to borders.

Troy Groetken ( is a shareholder at McAndrews. Troy has more than 15 years of experience in patent litigation and advanced prosecution matters in the IP field, and more than 20 years of experience in the pharmaceutical, biotechnological and chemical fields. Troy regularly counsels international and Fortune 100 clients.

Scott McBride ( is a shareholder at McAndrews, Held & Malloy. Scott has more than 15 years of experience in patent litigation and works with a wide array of technologies, with an emphasis on the life sciences, including medical devices and biotechnology.

Originally published on

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