Arista Networks Inc. uses technology owned by Cisco Systems Inc. in networking gear made in Asia, a U.S. trade agency ruled in a patent case, setting the stage for an import ban. The ruling Thursday by the U.S. International Trade Commission leaves Arista with the choice of asking the Obama administration to veto the import ban, or request that an appeals court throw out the case. “Arista respects the commission’s decision and intends to fully comply with the orders,” said Marc Taxay, general counsel for Arista. The company has released new versions of software that it believes address the ITC’s findings and will ask regulators to approve them, he said in a statement. Cisco claims that Arista, which was founded by former Cisco executives, has built its business using copied technology. It has filed multiple actions: the complaint decided Thursday, another case at the ITC, and a copyright-infringement suit scheduled for a November trial in California. Arista dropped 4.2 percent, to $70.73, in after-hours trading at 5:07 p.m. Arista has in turn accused Cisco of using unfair tactics to maintain its dominant position in the market. Trade Judge A trade judge in February said Arista infringed three of five patents held by Cisco, the world’s biggest networking-equipment maker. Arista maintained that it doesn’t infringe any Cisco patents in this or the other case. It’s filed challenges to the validity of the patents at the U.S. Patent and Trademark Office. Arista has been winning customers in one of Cisco’s most important businesses: the sale of machines called Ethernet switches used in data centers by Internet companies, banks and other large companies that are shifting to more cloud computing. Arista’s switches are based on software that is designed to be easier to use and more cost effective than Cisco’s IOS software, which has been almost as widely used by network administrators as Microsoft Windows is for running computers or Google’s Android for smartphones. Arista said the claim against its Sysdb product does not involve core architecture, but “external management.” A different judge is scheduled to release findings in the second ITC case brought by Cisco Aug. 26. The case is In the Matter of Certain Network Devices, Related Software and Components Therof, 337-944, U.S. International Trade Commission (Washington).