Seven Things Chinese Companies Should Consider When Pursuing U.S. Patent Protection

09 December 2009 Publication
Authors: Marshall J. Brown


By Marshall J. Brown, Foley & Lardner LLP

This article is part of our Winter 2009 edition of Legal News: China Quarterly Newsletter, Eye on China.

As Chinese companies become increasingly active in obtaining patent protection in the United States, it is important for these companies to consider many aspects of the U.S. patent laws that are unique to the United States. Some of these idiosyncrasies place particular burdens on inventors and attorneys, while others can provide unique opportunities to sophisticated patentees in various situations.

The following are a number of unique aspects of U.S. patent laws that should be considered by foreign companies when pursuing patent protection in the United States.

Absolute Novelty Is Not Required

Unlike most countries, the United States does not require that a utility patent application be filed before the underlying invention is disclosed in a printed publication or is otherwise disclosed to the public. Under U.S. law, a patent application may be filed up to 12 months after an invention is first described in a printed publication, is in public use in the United States, or is offered for sale in the United States. It is therefore possible to obtain utility patent protection in the United States, even if the underlying invention has been previously disclosed.

The United States Is a “First to Invent” Country

The United States is the only country that is based on a “first to invent” rather than a “first to file” system. Under this system, if two parties file U.S. patent applications describing the same invention, the second party to file an application may be awarded a patent over the first party, if the second can establish that it invented the claimed subject matter first. Additionally, an applicant can “swear behind” some types of prior art if it can establish an earlier date of invention.

Determining a date of first invention can be very difficult, and documentary evidence is very important in making such a determination. It is therefore important for inventors and companies to keep thorough records of their research and development activities, as this information may be critical in proving an earlier date of invention than another party or reference.

The Duty of Disclosure Requirement

Everyone associated with the filing and prosecution of a U.S. patent application has a duty to disclose to the U.S. Patent and Trademark Office (USPTO) all information that is “material to patentability.” As part of this requirement, all relevant prior art patents, publications, offers for sale, and so forth that are known to the applicant must be disclosed to the USPTO. This duty applies to many parties, including the inventors, their U.S. patent attorneys, and even foreign patent counsel. Because there is no similar requirement in most countries, it is especially important to inform local inventors and attorneys of this requirement, as a failure to disclose material prior art can render the resulting patent unenforceable.

Precise Support for Claim Language Is Not Required

In many countries, an applicant is not permitted to use language in a claim that does not also appear in the specification. The United States does not have such a stringent requirement, instead requiring only that claim language have express, implicit, or inherent support in the application as originally filed. This can provide an applicant with added flexibility when drafting claims. For example, an applicant can claim a feature that was not originally described in the specification but was shown in the original figures.

“Means-Plus-Function” Language Is Narrowly Construed

Although U.S. law permits applicants to describe structural limitations in a claim as a “means” for performing a function recited in the claim, this language will be narrowly construed during subsequent enforcement actions. Under U.S. law, this language will be limited to cover only the corresponding structure that is described in the specification as well as equivalents thereof. Additionally, if a court finds that corresponding structure is not sufficiently described in the specification, the entire claim can be found invalid. It is therefore sometimes advisable to include at least some claims that do not use any “means-plus-function” language, and if such language is used, it is important to ensure that corresponding structure is clearly discussed and identified in the specification.

Unlimited Continuation Applications Are Permitted

Applicants may file an unlimited number of continuation applications within the USPTO, so long as each continuation application is filed during the pendency of a related application. This can be helpful if a competitor is attempting to design around your patent claims. By filing a continuation application, you can continue to attempt to obtain broad patent claims, including claims that may cover competitors’ later-developed designs.

It Is Possible to Broaden Claims Post-Issuance

Even after a patent has granted, and no continuation application is filed, one can enlarge the scope of the patent’s claims in some circumstances. A patent owner can file a “reissue” application in order to correct an error or mistake in a granted patent. Importantly, such mistakes can include drafting patent claims too narrowly, and if a reissue application is filed within two years of the patent’s issuance, the patent owner is permitted to broaden the scope of the claims. A reissue application can therefore be a valuable tool if a competitor has designed around the claims of an issued patent, as it can provide the patent holder with another opportunity to obtain claims that are infringed.


As detailed above, there are both dangers and opportunities associated with many unique aspects of the U.S. patent laws. In the case of potential dangers such as the duty to disclose material prior art and the first to invent rule, inventors and other important personnel need to be made aware of these requirements in order to help prevent adverse findings against your patents. In other areas such as the 12-month post-disclosure window for filing new applications and the ability to broaden claims through reissue applications, U.S. laws provide companies with opportunities that are likely not available in other countries. A firm understanding of these and other aspects of U.S. patent practice is therefore important if your company wishes to greatly benefit from its U.S. patent procurement efforts.

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