Click here to view image.

Schrader-Bridgeport International, Inc. et al. v. Continental Automotive Systems US, Inc., IPR2013-00014 (Patent Tr. & App. Bd. 2014)

In a recent inter partes review (IPR) decision, Schrader-Bridgeport International, Inc. et al. v. Continental Automotive Systems US, Inc. (IPR2013-00014, Paper No. 32, entered March 12, 2014), the Patent Trial and Appeal Board held claims 1-5 and 7-11 of U.S. Patent No. 6,998,973 (the “’973 patent”) unpatentable as being obvious under 35 U.S.C. § 103.  Id. at 2 and 4.  With this decision, the PTAB has shown that it is open to combining prior art references in a similar manner to ex parte prosecution.

The ’973 patent is directed to a method of transmitting data in a tire-pressure monitoring system of a vehicle.  The feature at issue is “a natural time lag between various internal clocks with which each wheel unit is equipped is used to prevent collisions between transmissions from the various wheel units of one and the same vehicle” as recited in claim 1 of the ’973 patent.  Id. at 4.  Claims 2-5 and 7-11 all depend from independent claim 1.

Claim 1 of the ’973 patent purports to provide a method of transmitting data to prevent the collision of data during transmission from sensors in each of the wheel units.  In order to accomplish this, the claimed invention has a natural time lag between clocks in each of the wheels.  The ’973 patent explains that in order to provide this natural time lag, the clocks must have poor precision to incorporate a time lag between the transmission of data from each of the wheels.  The ’973 patent, col 2., ll. 20-24 and col. 3, ll. 55-58.

The Board determined the ’973 patent was unpatentable under 35 U.S.C. § 103(a) as being obvious over prior art references to Derbyshire, Bailie, and Bowers.

In its decision, the PTAB explained that a primary reference need not recognize the problem being solved by the patent at issue. Schrader-Bridgeport at 9.  For example, Derbyshire discloses a tire monitoring system having an internal clock and acknowledged that clocks in general can have varying degrees of accuracy, but did not address the problem of colliding data transmissions as stated in the ’973 patent.  Id. at 7.  The Board further held that a second reference may be combined to make up for this deficiency. Id. at 9.  Bailie discloses a system for data communication in a tire pressure monitoring system, recognizing the problem of data collision during transmission, and providing several methods for solving the problem.  Id. at 9.

Neither Derbyshire nor Bailie discloses addressing the data collision issue by using clocks having a natural time lag.  However, the Board held that Bowers, which discloses a method of reading RFID tags, including a technique to prevent data collision by constructing the RFID tags with components that have a low tolerance and thus are less precise, could properly be combined with Derbyshire and Bailie to obviate the ’973 patent.  Id. at 8.

The Patent Owner Continental’s Arguments

Continental made several arguments against the combination of the references.  First, Continental argued that there was no reason to combine the references. Id. at 10.  However, the Board dismissed this argument, stating that Bowen’s approach is a known, viable option from a limited number of techniques, i.e., an obvious to try rationale. Id. at 12-13.

In addition, Continental stated that Derbyshire teaches against combining with Bowers, arguing that Derbyshire required the use of high tolerance components.  Id. at 13.  However, the Board found this argument unpersuasive because Derbyshire only required high tolerance components in “some applications,” suggesting that not all applications require high-tolerance components, and can instead use low-tolerance components.  Id. at 14.

Interestingly, Continental’s third argument against combining references was that Bowers is non-analogous art.  Specifically, Continental argued that Bowers was not analogous art because it did not address the problem of “prevent[ing] collisions of data from multiple transmission sources associated with tire pressure monitoring that is less expensive and less difficult to implement without compromising safety.”  Id. at 15, citing Patent Owner Response 31.  However, the Board disagreed with Continental’s assertion.  In citing Wyers v. Masters Lock Co., the Board stated that “[a] reference is analogous art if it is either: (1) in the field of the inventor’s endeavor; or (2) is ‘reasonably pertinent’ to the particular problem with which the inventor was concerned.”  616 F.3d 1231, 1238 (Fed. Cir. 2010).

While the Board acknowledged that the Bowers reference, which disclosed RFID tags, was likely not in the field of tire monitoring, the Board nonetheless found that Bowers had an analogous function.  Schrader-Bridgeport at 16.  Because Bowers  was “concerned with preventing data collision among multiple, substantially simultaneous transmission in a manner that addresses ‘cost ‘ issues,” the PTAB determined that the disclosure of Bowers was “reasonably pertinent”  to the collision of data during transmission and that the combination of Bowers with Derbyshire and Bailie was proper.  Id.

Finally, Continental argued that Bailie required a “vetted” approach while Bowers required an “unvetted approach.”  Id. at 17.  The Board was not clear about Continental’s statement, but understood the argument to relate to the way in which the data in Bailie was transmitted.  In discounting the argument, the Board determined that Bailie disclosed multiple “patterns” by which the data could be transmitted and a person of ordinary skill in the art would understand that Bailie was not “vouching for the efficacy of a particular pattern.”  Id. at 18.

The Board did not have difficulty finding reasons to combine the references in this inter partes review and has shown that it is open to combining references in a manner similar to that applied by Examiners and the PTAB in ex parte prosecution.  The PTAB’s willingness to find reasons to combine references bodes well for IPR Petitioners challenging the patentability of claims.