In the ongoing patent battle between Cisco and Arista, an International Trade Commission (ITC) judge ruled Dec. 9 that Arista infringed on some of Cisco’s patents in a second ITC investigation.

Administrative Law Judge Mary Joan McNamara issued an initial determination in case No. 337-TA-945, finding that Arista infringed two of Cisco’s patents. Cisco’s original complaint in case '945 alleged that Arista’s products infringed six patents, but the judge found no violation with respect to four of them.

Arista intends to request a review of the findings. At the same time, it intends to address the infringement findings with design-arounds for its products.

This is the same approach Arista took in relation to the first ITC patent case (No. 944) filed by Cisco. It created software workarounds that brought its products into compliance, thus saving them from being banned from importation. (Tech products tend to be built and/or assembled overseas, which is why the ITC can get involved in these patent disputes.)

In case '944, the U.S. Customs and Border Protection agency recently ruled that Arista’s redesigned products could be imported into the U.S.

Separately, Cisco and Arista this week are sparring in a trial in U.S. District Court in San Jose, California. In that copyright lawsuit, Cisco claims Arista’s use of command-line interface (CLI) commands is a violation.

The case involves the testimony of top level executives from both Cisco and Arista, highlighting the bad blood and personal animosity between the leaders of the two rival companies. The trial could produce a jury verdict this week.

A page on Arista’s website summarizes all the dates related to the Cisco patent legal actions.