IP Law Daily Location monitoring solutions provider could have infringed patent for tracking system marketed to hospitals
Thursday, February 14, 2019

Location monitoring solutions provider could have infringed patent for tracking system marketed to hospitals

By Thomas Long, J.D.

A district court erred in granting summary judgment to the defending provider on the grounds that the asserted claims were invalid for lack of written description and were not infringed by the provider’s system.

There were genuine issues of material fact as to whether claims of a patent directed to systems for locating and identifying portable devices using ultrasonic base stations, owned by CenTrak, Inc., were invalid for lack of written description or were not infringed by competitor Sonitor Technologies, Inc., making summary judgment inappropriate as to both questions, the U.S. Court of Appeals for the Federal Circuit has held. The appellate court reversed a decision of the federal district court in Wilmington, Delaware. With respect to written description, the patent’s specification could have contained enough information about the use of ultrasonic signals to convey to a skilled artisan that the inventors had possession of tracking systems that could use ultrasound. As for noninfringement, the appellate court concluded that there was enough evidence to raise a triable issue of fact as to whether Sonitor infringed as a "final assembler" of its customers’ tracking systems, using certain hardware and software components that were already on-site (CenTrak, Inc. v. Sonitor Technologies, Inc., February 14, 2019, Chen, R.).

Patent-in-suit. CenTrak’s U.S. Patent No. 8,604,909 ("the ’909 patent"), entitled "Methods and Systems for Synchronized Ultrasonic Real Time Location," related to systems for real-time location (RTL), which allow users to locate and identify portable devices in a facility. CenTrak provided its RTL systems to healthcare facilities, such as hospitals, which used it to track equipment and patients. The asserted claims recited the use of ultrasonic base stations; portable devices (tags); a server; radio frequency (RF) base stations; and a backbone network that connects the server with the RF base stations. Although all claims of the ’909 patent recited "ultrasonic" components, the vast majority of the specification focused on infrared or RF components, except for two sentences.

Accused products. Sonitor made and sold an RTL system called "Sonitor Sense," which included three pieces of hardware: RF "gateways," ultrasonic location transmitters, and portable locator tags. Sonitor also provided related software. CenTrak asserted that the Sonitor Sense system infringed the ’909 patent when these components are integrated with a customer’s existing network and server hardware. Specifically, CenTrak accused Sonitor of infringing claims 1, 7, 8, 16, 18, 21, 22, and 26 of the ’909 patent. Because Sonitor did not sell all of the hardware needed to practice the patent claims, CenTrak pursued a theory under 35 U.S.C. §271(a) that Sonitor "makes" infringing systems when it installs and configures the Sonitor Sense system. Sonitor moved for summary judgment, asserting noninfringement and invalidity of the asserted claims.

Written description. Sonitor argued that the two sentences in the specification dedicated to ultrasound did not show that the inventors had possession of an ultrasound-based RTL system. The district court ruled that while the specification "contemplated" ultrasound, mere contemplation was not enough to meet the written description requirement. Reasoning that "electromagnetic radiation and sound waves are not simply two species of the same genus; rather these are two completely different types of phenomena" and that "one could not simply drop [an ultrasonic] transmitter into the system as disclosed in the specification and have a functioning [ultrasonic] system," the district court granted summary judgment that CenTrak’s claims did not satisfy the written description requirement.

The Federal Circuit noted that the test for sufficiency of a patent’s written description is whether the disclosure reasonably conveyed to skilled persons that the inventor had possession of the claimed subject matter as of the filing date. The specification must describe an invention that is understandable to the skilled artisan and show that the inventor actually invented it. Written description, the court explained, was about whether the skilled person could recognize that what was claimed corresponded to what was described, not whether the patentee had proven to the skilled reader that the invention worked (which was an enablement issue).

In this case, there were factual issues to whether disclosure of the implementation details that the district court identified is necessary to satisfy the written description requirement. The district court leaned heavily on the fact that the specification devoted less attention to the ultrasonic embodiment compared to the infrared embodiment. However, the Federal Circuit noted that there was case law standing for the proposition that a specification’s focus on one particular embodiment or purpose cannot limit the described invention where that specification expressly contemplates other embodiments or purposes. The ’909 patent’s specification at least mentioned base stations and receivers that used ultrasound, which made this case distinguishable from other cases in which the written description requirement was not met because the specifications in those cases made no mention of certain later-claimed limitations. The parties had disputed the complexity and predictability of ultrasonic RTL systems, and the district court erred at the summary judgment stage by not sufficiently crediting testimony from CenTrak’s expert that the differences between infrared and ultrasound, when used to transmit small amounts of data over short distances, were incidental to carrying out the claimed invention, the appellate court said. The Federal Circuit concluded that the district court erred in granting summary judgment because there was a material dispute of fact as to whether or not the named inventors actually possessed an ultrasonic RTL system at the time they filed their patent application.

Noninfringement. Sonitor’s main noninfringement argument was that Sonitor does not make, use, or sell certain elements recited in the claims, including the required backbone network, Wi-Fi access points, or server hardware. CenTrak responded that the party assembling components into the claimed assembly "makes" the patented invention, even when someone else supplies most of the components. Sonitor contended that the court should reject as untimely CenTrak’s argument that Sonitor’s role in the "final assembly" of the system resulted in infringement.

The district court granted summary judgment of noninfringement, holding that a defendant must be the actor who assembles the entire claimed system to be liable for direct infringement. Because CenTrak had not submitted proof that Sonitor personnel had made an infringing assembly, Sonitor could not have directly infringed, in the district court’s view.

The Federal Circuit determined that CenTrak had presented its infringement theories before the district court sufficiently to preserve the arguments for appeal. The appellate court disagreed with the district court’s conclusion that there was no triable issue of fact as to whether Sonitor made infringing systems. Although Sonitor did not provide certain claimed elements in the accused systems, CenTrak argued that the final, missing elements were already part of the customers’ own hardware, and that Sonitor was the "final assembler" of the accused systems because it provided the configuration that allowed the location transmitters to work with the network and the location codes that were entered into the server. In the appellate court’s view, a reasonable fact-finder could conclude that Sonitor infringed the asserted claims of the ’909 patent, although it also could not be determined on summary judgment that Sonitor did in fact infringe, because it was unclear on the record who installed each claimed element or completed an infringing combination. Therefore, the summary judgment ruling was reversed, and the case was remanded for further proceedings.

This case is No. 17-2510.

Attorneys: Jeffrey I. Kaplan (Kaplan Breyer Schwarz, LLP) for CenTrak, Inc. Jack B. Blumenfeld (Morris, Nichols, Arsht & Tunnell LLP) for Sonitor Technologies, Inc.

Companies: CenTrak, Inc.; Sonitor Technologies, Inc.

MainStory: TopStory Patent FedCirNews

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