Disavowal of Claim Scope Not Shown by a Multitude of Statements Which Can Be Interpreted as a Way of Making the Invention


Continental Circuits LLC, v. Intel Corporation, Case No. 2018-1076 (Fed. Cir. February 8, 2019)

Disavowal of Claim Scope Not Shown by a Multitude of Statements Which Can Be Interpreted as a Way of Making the Invention

Thomas Sexton

Decision: Continental Circuits LLC, v. Intel Corporation, 915 F.3d 788 (Fed. Cir. 2019) (precedential) (LOURIE, Linn, and Taranto)

Summary: The District Court found claim scope disavowal based on a collection of statements. The Federal Circuit treated the statements individually, saying for each individual statement, that the individual statement did not rise to the level of disavowal.

Background: Continental asserted claims for patent infringement . Continental's U.S. Patent No. 7,501,582 ("the '582 Patent", one of four patents asserted) is directed to a method of making a multilayer electrical device. The patents are the result of continuation applications and share a substantially identical specification. The patents include description of a dielectric etch process which creates teeth to improve a strength of bonding between layers. The etching process is called a desmear process. At issue was whether or not claim terms related to a surface, etching, or removal of dielectric material required a repeated desmear process.

A portion of FIG. 1 of the '582 Patent. "11" indicates the teeth.

Claim 100 reads:

100. An electrical device including: a conductive layer built up so as to fill undercuttings with respect to a surface of a dielectric material so as to form teeth in cavities, a plurality of the undercuttings being obtuse to the surface, wherein the conductive layer is a portion of circuitry of an electrical device, and a plurality of the teeth are within the range of 1 tenth of a mil deep to 1.75 tenths of a mil deep, and wherein at least one of the cavities includes an upgrade slope with respect to the surface of the dielectric material, and one of the teeth engages a portion of the dielectric material at the slope.

Intel argued that the asserted claims require a repeated desmear process based on disavowal. Intel's claim construction relied on statements in the patent specification and on an expert declaration filed during prosecution.

The District Court agreed with Intel based at least on the following points:

1. The '582 Patent states "One technique for forming the teeth is somewhat similar to what has been known as the swell and etch or desmear process, except that contrary to all known teachings in the prior art, in effect, a 'double desmear process' is utilized." '582 Patent 5:41-44.

2. The '582 Patent states "To carry out the present invention, it is preferable to use a palladium-based direct plate process or other non-electroless process…. the desmear process as disclosed herein is contrary to the manufacturer's specifications, i.e., a "double desmear process," rather than the single desmear process of the known prior art. Compare FIGS. 1, 2, and 9. " '582 Patent 5:57-64.

3. The '582 Patent states "the peel strength produced in accordance with the present invention is greater than the peal strength produced by the desmear process of the prior art, i.e., a single pass desmear process. " '582 Patent 7:3-9.

4. The '582 Patent states "Although Probelec XB7081 apparently was intended for use in the common desmear (swell and etch) process as used in conventional plated through hole plating lines, Probelec XB7081 can alternatively be used in carrying out the present invention. For example, the present invention differs from the common desmear process in that sub-steps in the desmear process are repeated as a way of forming the teeth." '582 Patent 8:45-52.

5. The '582 Patent states "In stark contrast with the etch and swell process of the known prior art, however, a second pass through the process (sub-steps A through F) is used. The second pass seems to make use of non-homogenaities in bringing about a formation of the teeth. " '582 Patent 9:1-9.

6. In response to a rejection under 35 U.S.C. § 112, the applicant submitted an Expert Declaration describing the teeth of FIG. 1 and of the claims. The Expert Declaration described the teeth as formed in a two-pass process. The Expert Declaration states: "performing two separate swell and etch steps is a technique which forms the teeth. … By forming the irregular releases in the first etching pass, an opening within the dielectric material would then be enlarged in the second etch pass, making the structure shown in Figure 1 and recited in the claims[.]" See the '582 Patent file history at March 2, 2007 for a copy of the expert declaration.

7. Some dependent claims explicitly recite a repeated desmear process. The Patentee argued that, based on claim differentiation, the independent claims are not limited to a repeated desmear process. The District Court noted that claim differentiation is only a "rule of thumb."

Issue on Appeal: Do the claims require that the dielectric material be formed by a repeated desmear process?

Outcome: Vacated and Remanded: Patentee did not disavow a single desmear process.

The District Court's claim construction was disputed. The Federal Circuit agreed with Continental that the District Court erred in limiting the claims to require a repeated desmear process. The Federal Circuit found that none of the statements relied upon rises to the level of a clear and unmistakable disclaimer.

The Federal Circuit pointed out language in the specification at 5:40-44 stating that "One technique for forming the teeth is somewhat similar to what has been known as the swell and etch or desmear process, except that contrary to all known teachings in the prior art, in effect, a 'double desmear process' is utilized." The Federal Circuit collected various statements from the specification, and characterized them as describing how to make the claimed invention. The Federal Circuit found that phrases in the specification such as "one technique," "can be carried out," and "a way" indicate one method for making the invention and do not automatically lead to a finding of clear disavowal of claim scope. The Federal Circuit also noted that claims need not be limited to a single embodiment when the specification contains only the single embodiment.

The Federal Circuit also found that clearly describing a particular claim term to overcome an indefiniteness or written description rejection is not the same as disavowing claim scope.

Practice Tips: This case illustrates that providing a number of ways of describing an embodiment is helpful to avoid suffering a disavowal of claim scope.

Based on this Federal Circuit decision, an applicant may file an expert declaration describing a particular manufacturing technique of producing a feature of the claims without limiting the claims to that particular manufacturing technique.

To avoid a close call in claim construction, include detailed descriptions of at least two embodiments in the specification in order to make it more difficult for a party to argue that the claims are limited to the only embodiment disclosed.