Maryland Bar Bulletin
Publications : Bar Bulletin : March 2013


Claim construction is the most important aspect in patent litigation.  In fact, the Federal Circuit Court stated, in re Hiniker Co. (1998), “[t]he name of the game is the claim.”

In this regard, in Phillips v. AWH, the court set forth several guidelines on how to interpret the disputed claims. Phillips tells us that the “bedrock principle” of patent law is that the claims of the patent define the invention. Accordingly, the words of a claim are generally given their ordinary and customary meaning. The court also emphasized the importance of the specification in interpreting the claims, while cautioning against importing limitations from the specification into the claims. Specifically, the court warned against limiting the claims to the specific embodiments disclosed in the specification. 

The cases after Phillips indicate that there is a split in the Federal Circuit and the other courts regarding the role of the specification in interpreting the claims.

Some panels declined to change the terms of the claims based on the specification, while other panels deferred to the specification and accorded a meaning consistent with the specification. 

This divide is clearly played out in a recent Federal Circuit decision, Retractable Techs., Inc. v. Becton Dickinson & Co. The patents at issue are related to retractable syringes with a needle that retracts into the body of the syringe after use. This prevents the hazards associated with exposed, contaminated needles. Both Retractable Technologies (“RTI”) and Becton Dickinson (“BD”) sell syringes with retractable needles.  RTI sued BD for infringement of U.S. Patent Nos. 5,632,733 (the ‘733 patent), 6,090,077 (the ‘077 patent), and 7,351,224 (the ‘224 patent).

The parties disputed the meaning of the term “body” as recited in the claims.  Based on the “plain and ordinary meaning” of the term, the district court concluded that the term “body” is not limited to one-piece structures. A jury trial found that the patents are not invalid, and are infringed by BD’s sale of retractable syringes.

It is notable that an independent claim of the ‘224 patent recites the term “body,” while a dependent claim limits “body” to a “one-piece body.” According to the claim differentiation doctrine, this indicates that the term “body” includes structures other than “one-piece body” structures.

On appeal, BD argued that the district court erred by not limiting the term “body” to one-piece structures because the specifications describe the “invention” as including a one-piece body, and criticize the prior art two-piece syringes. According to BD, the claim differentiation doctrine does not apply because of these limiting statements in the specifications. 

The Federal Circuit agreed with BD. The court stated that although the dependent claims recite a “one-piece body,” none of the claims recites a body with multiple pieces.  The court noted that in several places in the specifications, it is stated that this “invention” is a one-piece body. Additionally, all the embodiments and figures depict a one-piece body. The patents failed to disclose any structures with multi-piece bodies. Accordingly, the court concluded that the term “body” included only one-piece body structures.  Based on this interpretation, the court reversed the district court’s decision that BD’s sale of retractable syringes infringed the patents at issue.

Chief Judge Randall R. Rader, in his dissent, pointed out that the patentee never disavowed that the scope of the term “body” includes multi-piece structures. According to the dissent, based on the claim differentiation doctrine, the term “body” included alternate, multi-piece structures.               

This case stresses the importance of the patent specification and the need to consider how the disclosure and the claims will be viewed in the eyes of courts, competitors, and potential infringers when drafting an application. Often, the embodiments described in a specification are directed to one specific feature or purpose encompassed by the broader invention claimed. Where possible, care should be taken to avoid limiting language such as statements that “the invention is” directed to one particular feature or purpose, or otherwise the patentee runs the risk that courts interpret the claims narrowly. 

To the extent possible, the specification should include alternate embodiments that cover potential workarounds that clever competitors may design to avoid falling under the scope of a claimed invention. In retrospect, RTI may have avoided the court’s claim interpretation by including “hedging” language that the aspects of the invention may also include syringes with multi-piece bodies, and describing these alternate embodiments sufficiently to satisfy the enablement, written description, and definiteness requirements of 35 U.S.C. § 112. Even though this may further burden the specification drafting process, it is advisable to err on the side of caution. 

Murray Spruill, Ph.D., is a partner with the Alston & Bird LLP. Namal C. Warshakoon, Ph.D., is an associate with the Alston & Bird LLP.

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Publications : Bar Bulletin : March 2013

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