On 28 April 2016, Bombardier Aerospace recorded a firm order from Delta Air Lines for 75 CSeries CS100s plus 50 options. On 27 April 2017, Boeing filed a petition for dumping them at 19.6meach,belowtheir19.6m each, below their 19.6meach,belowtheir33.2m production cost. On 9 June 2017, the US International Trade Commission (USITC) found that the US industry could be threatened.On 26 September, the US Department of Commerce (DoC) observed subsidies of 220% and intended to collect deposits accordingly, plus a preliminary 80% anti-dumping duty, resulting in a duty of 300%.The DoC announced its final ruling, a total duty of 292%, on 20 December.On 10 January 2018, the Canadian government filed a complaint at the World Trade Organization against the US. On 26 January 2018, the four USITC commissioners unanimously determined that US industry is not threatened and no duty orders will be issued, overturning the imposed duties.The Commission public report was made available by February 2018.On March 22, Boeing declined to appeal the ruling. While the USITC had determined there was no threat, the ruling came too late for Bombardier, as the dumping petition by Boeing had already paved the way for Bombardier to relinquish a controlling interest in the CSeries to Airbus in October 2017. (en)