The case began in January 2015 after the woman's husband, Lloyd Carl Field Jr, was killed during an incident that took place the previous November. Court documents on the woman's side claimed that "Twitter has knowingly permitted the terrorist group ISIS to use its social network as a tool for spreading extremist propaganda, raising funds and attracting new recruits. This material support has been instrumental to the rise of ISIS and has enabled it to carry out numerous terrorist attacks."

The appeals court, however, ruled 3-0 that the families failed to demonstrate a direct link between Twitter's services and the death of the contractors. Circuit Judge Milan Smith said: "Communication services and equipment are highly interconnected in modern economic and social life, such that the provision of these services and equipment to terrorists could be expected to cause ripples of harm to flow far beyond the defendant's misconduct. Nothing in [the law] indicates that Congress intended to provide a remedy to every person reached by these ripples."

The verdict upholds a previous ruling from August 2016, but the families' lawyer Joshua Arisohn said his clients were now weighing up their legal options. "Requiring a more direct connection between the provision of material support to terrorists and the attacks that they carry out contravenes the central purpose of the Anti-Terrorism Act: holding enablers of terrorists accountable," he said. Other companies have also been hit with legal action related to extremist activities on their websites. While none has been successfully sued, these proceedings do call into consideration their dubious position in anti-terrorism matters, and put question marks over how long they'll be able to rely on court precedents like this one.