By Dennis Crouch
Intellectual Ventures I LLC v. T-Mobile USA, Inc. (Fed. Cir. 2018)
Delaware Chief Judge Stark ruled on summary judgment that T-Mobile did not infringe IV’s U.S. Patent No. 6,640,248. The district court also found claim 20’s means-plus-function limitation left that claim indefinite. On appeal, the Federal Circuit reversed claim construction and thus vacated on non-infringement — however, the court affirmed on indefiniteness.
Indefiniteness: The indefiniteness doctrine is codified within 35 U.S.C. 112(b), which requires each claim be “particular” and “distinct.” The Supreme Court’s most recent statement on the doctrine requires that claims delineate their scope with “reasonable certainty.” Although I have not checked into the stats recently, my somewhat educated prior is that the district courts have followed the Federal Circuit’s lead in usually giving issued patents a ‘pass’ on definiteness — much like utility. The one major exception is the area of of means-plus-function claims.
35 U.S.C. 112(f) allows for claims to include particular elements “expressed as a means … for performing a specified function without the recital of structure, material, or acts in support thereof.” However, when MPF style is used the Federal Circuit requires that at least one example of a the corresponding omitted structure be described within the patent specification. When no corresponding structure is provided, the respective claim is deemed invalid as indefinite.
This case involved a means-plus-function that rendered a claim indefinite — but the court did not actually reach the question of corresponding structure. Rather, the court determined that the claimed function was too ambiguous.
IV’s asserted claims are directed to a network system designed for non-net-neutrality applications. When allocating network resources, the system will consider the quality of service (QoS) needed for a particular application and allocate resources (bandwidth) to prioritize speed where needed. Claim 20 requires an “allocating means for allocating resources to said IP flow … so as to optimize end user application IP QoS requirements of said software application.”
The district court found the claimed function indefinite. In particular, the court noted that specification’s description of QoS as “subjective” according to a user’s “individual preferences” and that description lacked “adequate guidance as to the meaning of ‘optimize.'”
On appeal, the Federal Circuit presumably performed a de novo review, but affirmed — particular zeroing in on its precedent requiring “objective boundaries.” Interval Licensing LLC v. AOL, Inc., 766 F.3d 1364, 1371 (Fed. Cir. 2014) (“The claims, when read in light of the specification and the prosecution history, must provide objective boundaries for those of skill in the art.”). Here, the court interpreted “optimizing QoS” as akin to the invalid “aesthetically pleasing” limitation of Datamize, LLC v. Plumtree Software, Inc., 417 F.3d 1342 (Fed. Cir. 2005). According to the court, both elements are “purely subjective” and depend wholly upon each user’s personal opinions.
We see no error in the district court’s conclusion that this function is indefinite or that because the function is indefinite, there was no need to evaluate structure. We have similarly held a means-plus-function limitation indefinite without looking to structure where a term of degree in the function was sufficient to render the claim indefinite.