IP Law Daily, PATENT—Fed. Cir.: Computer memory read interface protocol patent is invalid for anticipation, (Dec 13, 2023)

By Thomas Long, J.D.

Although the invention’s preferred embodiment described use of a single component—and the prior art used two—nothing in the patent itself limited the invention to one physical structure.

Substantial evidence supported a decision by the Patent Trial and Appeal Board that a patent for a computer memory read interface protocol was invalid for anticipation by prior art, the U.S. Court of Appeals for the Federal Circuit has decided. The sole prior art reference relied on by the Board in its inter partes review decision met the limitations of the challenged patent claims even though the method of the prior art patent described two physically separate components, while the preferred embodiment contained only a single structure. The Federal Circuit agreed with the Board that nothing in the claims or the specification of the patent at issue required that the claimed storage device be limited to only one component (Monterey Research, LLC v. Vidal, December 13, 2023, Clevenger, R.).

Patent at issue. The patent at issue, U.S. Patent No. 6,629,226 (“the ’226 patent”), owned by appellant Monterey Research, LLC, was titled “FIFO Read Interface Protocol.” It related to a system of electrical circuits for storing data packets in a buffer memory and retrieving and moving those packets when a computer, disk drive, or other such logic system (referred to as a “host system”) cannot receive them due to insufficient memory or a busy network. “FIFO” stands for “first-in, first-out”; the patented invention described a method and architecture for using a multiqueue FIFO memory read interface to address synchronization problems and to allow for management of “variable-sized data packets.”

Invalidity decision. Advanced Micro Devices, Inc., petitioned for inter-partes review of the ’226 patent, on grounds of anticipation and obviousness. The Board determined that the challenged claims were unpatentable as anticipated U.S. Patent No. 4,949,301 (“Joshi”). The Board’s decision depended on its construction of the claim term “‘multiqueue storage device’ as ‘a storage device having data organized into multiple queues,’ without any limitation on the logic or component that organizes or manages the queues—whether that logic or component is internal or external to the multiqueue storage device.”

According to the Board, Joshi disclosed a “multiqueue storage device” that was “configured to generate an address request signal.” It also determined that the invention described in Joshi contained an “interface” that the “multiqueue storage device” was coupled to. Therefore, although there were intervening steps in the process detailed by Joshi, the prior art reference disclosed a “multiqueue storage device [] configured to generate an address request signal” because its signals ultimately caused one component to send the next packet address to one of the components comprising the multiqueue storage device.

Anticipation. Monterey Research appealed, arguing before the Federal Circuit that that Joshi did not disclose “an interface coupled to a multiqueue storage device” because the two components noted by the Board could not together be considered a “multiqueue storage device.” The court reviewed the Board’s decision for substantial evidence and affirmed. In the court’s view, the Board reasonably concluded that nothing in the ’226 patent indicated that a “multiqueue storage device” must be one physical component. The Board also reasonably determined that nothing in the patent required any minimum level of access between multiple components to be considered one device.

The Federal Circuit said that it would not impute the requirement of a “unified physical structure” when the patent at issue did not require one, even though the only preferred embodiment in the claimed invention showed a single physical structure. Noted the court, the ’226 patent’s specification stated, “While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention.”

Accordingly, the court held that the Board’s conclusion that the ’226 patent was anticipated by Joshi was supported by substantial evidence.

The case is No. 22-1577.

Attorneys: Donald Lee Jackson (Rimon, PC) for Monterey Research, LLC. Benjamin T. Hickman, U.S. Patent and Trademark Office, for Katherine K. Vidal.

Companies: Monterey Research, LLC

Cases: Patent FedCirNews