IP Law Daily, PATENT—Fed. Cir.: Challenged claims of two Cupp Computing firewall security patents are obvious, (Oct 26, 2022)

By Cheryl Beise, J.D.

PTAB erred in finding that a prior art reference did not teach the “dynamically isolating” limitation disclosed in three challenged claims.

Substantial evidence did not support the Patent Trial and Appeal Board’s finding that three challenged claims of two Cupp Computing firewall security patents were not invalid as obvious, the U.S. Court of Appeals for the Federal Circuit has determined. Under the Board’s undisputed claim construction, a key prior art reference clearly disclosed the “dynamically isolating” limitation in the challenged claims (Trend Micro, Inc. v. Cupp Computing AS, October 25, 2022, Taranto, R.).

Trend Micro Inc. filed petitions seeking inter partes reviews (IPRs) of certain claims of two patents owned by CUPP Computing AS—claims 1, 7, and 16 of U.S. Patent No. 8,365,272 and claims 1, 6, and 7 of U.S. Patent No. 9,756,079. Both patents are titled, “System and method for providing network and computer firewall protection with dynamic address isolation to a device.” The ’272 patent is the grandparent of the ’079 patent. The patents describe providing a system and method for providing data and device security between external and host devices. The ’272 specification discusses aspects of communication between (a) a computer (or a particular application on the computer) that is part of a particular network (e.g., the computer’s home network) and (b) computers or applications outside that network (e.g., on a public network).

In its IPR petitions, Trend Micro asserted that the claims are unpatentable under pre-AIA 35 U.S.C. § 103 because their subject matter would have been obvious, at the relevant priority date in 2007, over certain combinations of prior-art references, including WO2006/069041 (Sikdar), which was published on June 29, 2006. The PTAB instituted the requested reviews and issued final written decisions holding each claim 1 to be unpatentable but rejecting Trend Micro’s challenges to claims 7 and 16 of the ’272 patent and claims 6 and 7 of the ’079 patent.

Trend Micro appealed the Board’s holding regarding claims 7 and 16 of the ’272 patent and claim 7 of the ’079 patent.

Appealed claims. The parties agreed that the claims at issue on appeal (claims 7 and 16 of the ’272 patent and claim 7 of the ’079 patent) specifically address outgoing communications from a computer application to addresses in networks that are external to the originating network, with such communications including a source address (useful to enable an eventual reply) and a destination address. In particular, the claims recite “dynamically isolating” the internal address of a computer application from an external network by translating the application’s internal address so as to include a different origination address in the message sent to a computer outside the home network.

“Dynamically isolating” limitation. The only issue on appeal was whether Sikdar teaches the “dynamically isolating” limitation of claims 7 and 16 of the ’272 patent and claim 7 of the ’079 patent. The parties did not dispute the Board’s construction of “dynamically isolating” as “including the use of DHCP or other source of addresses in connection with a NAT [Network Address Translation] engine to translate IP addresses.”

Sikdar discloses a Reconfigurable Semantic Processor (RSP) capable of performing NAT. The RSP “can be programmed for NAT/PAT operations that convert IP addresses and/or port numbers for packets traveling thru the firewall 1062 between public IP addresses that are used for transporting the packet over public network 12 and private IP addresses that are used for transporting the packet over the private network 24.”

Applying the Board’s claim construction, the Federal Circuit found that Sikdar teaches the “dynamically isolating” limitation. Sikdar discloses “the use of DHCP or other source of addresses in connection with a NAT engine to translate IP addresses.” The Board’s construction simply requires any source of addresses—“DHCP or other source of addresses.” Sikdar teaches this aspect of the claim construction in several ways, the court observed. Sikdar discloses that the SPU “generates” the public IP address, says that this address is “usually” the address “assigned to” the firewall, and describes, in an alternative embodiment, a one-to-one mapping of private and public addresses. “These disclosures teach a ‘source of addresses in connection with a NAT engine to translate IP addresses,’” the court said.

The court concluded that Sikdar discloses “the use of DHCP or other source of addresses in connection with a NAT engine to translate IP addresses.” The Board erred by relying on the firewall-only reading of Sikdar. “But even if Sikdar were limited to using an unvarying public IP address (of the firewall), it still falls within the claim construction, which nowhere requires variability of the swapped-in public IP address from packet to packet,” the court said.

The Federal Circuit vacated the Board’s decisions and remanded for further proceedings.

The Case is No. 20-2237.

Attorneys: Stanley Joseph Panikowski, III (DLA Piper LLP) for Trend Micro Inc. James R. Hannah (Kramer Levin Naftalis & Frankel LLP) for Cupp Computing AS.

Companies: Trend Micro Inc.; Cupp Computing AS

Cases: Patent TechnologyInternet FedCirNews