Boeing stated the decision validated its complaints about Bombardier's aircraft pricing in the United States, "pricing that has harmed our workforce and USA industry".
Commerce Secretary Wilbur Ross said the decision was based on a "full and unbiased review of the facts in an open and transparent process".
The decision follows the DoC's preliminary recommendation of duties on Bombardier's C Series jets earlier this fall.
The US government made a decision to affix high anti-subsidy tariffs on the Bombardier's CSeries jets, after Boeing Co complained that the Canadian company had received unfair subsidy from their government which, it argued, allowed Bombardier to sell their new aeroplane below cost.
"The United States is committed to a free, fair, and reciprocal trade and will always stand up for American workers and companies being harmed by unfair imports", he said in a news release.
The decision also included language that could disrupt Bombardier's plan to circumvent the tariff by completing final assembly of CSeries aircraft ordered by USA airlines in Mobile, Alabama.
The Commerce Department's decision comes as the Trump Administration takes a hard line on trade practices it views as hurting American workers.
No planes have yet entered the United States.
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The White House pushed back against The Post's report . "We stand by our reporting", Dawsey said . "I never even wavered and am very proud of him and the job he is doing as a Justice of the U.S.
The International Trade Commission will make its final injury determination by February 1, and if injury is found, Commerce will issue AD and CVD orders. The trade dispute stems from a complaint by USA aerospace giant Boeing against its Canadian rival that found a receptive ear in President Donald Trump, whose "America First" agenda has included taking a tough line in matters of global commerce.
"Today the US Department of Commerce reaffirmed the magnitude to which Bombardier has been subsidized by government funds and the extent to which it dumped C Series aircraft in the United States, selling those aircraft at prices millions below production cost in an illegal effort to grab market share in the US single-aisle airplane market", it said in a statement.
There is more information on the U.S. department of commerce decision here.
Boeing argues that Bombardier signed a deal to sell its new single-aisle CS 100 planes with a price tag of just $19.6 million each, far below the $33.2 million construction cost, and a pittance compared with the list price of $79.5 million - though that amount is nearly never paid.
"There's no case here", Bombardier's Bellemare said, calling the complaint "ridiculous".
Delta plans to use the fuel-efficient but small mainline aircraft to operate flights to a broader array of midsize markets than it can efficiently do with its present fleet.
Boeing, she said, is seeking to "advance its market dominance by excluding Bombardier's C Series aircraft from the USA market".
The question now before the ITC is whether those improper benefits injured Boeing in the 100-150-seat market for commercial aircraft.