In the United States, more than 100 technology companies, including Apple, Google, Facebook and Microsoft have filed an amicus curiae brief, arguing against US President Donald Trump's ban on refugees and travel from seven predominantly Muslim nations. The joint brief has been filed in the US 9th Circuit Court of Appeals in support of a Washington judge's move to halt enforcement of the executive order. The brief contends that the ban is unconstitutional, unfair and bad for business.<br/><br/>The filing comes after a week of activism from tech firms, whose industry emerged as the first and loudest corporate opponent of Mr Trump's order. Other high-profile companies that haven't signed the brief include IBM and Oracle, both of which have executives on the new US Pesident's panel.