Boeing says its trade complaint against Bombardier is designed to prevent the Montreal-based rival from using subsidies to produce a larger version of the CSeries plane that would directly compete with its own flagship narrowbody 737 aircraft.

Last week, Boeing filed a document with the U.S. International Trade Commission that sheds new light on the trade dispute between the two aerospace manufacturers.

In the 109-page filing, Boeing says Bombardier would be positioned to build a full-fleet of single-aisle planes — repeating a strategy employed by French aerospace company Airbus — if Canadian subsidies to Bombardier are left unaddressed.

Bombardier (TSX:BBD.B) says in a separate filing that Boeing's effort to shut down its innovative technology from the market is "misguided," adding that Boeing's complaint is tantamount to asking the U.S. International Trade Commission to imagine a hypothetical world in the future.

The company says its CSeries commercial jet isn't an imminent threat to Boeing because the first planes won't be delivered to Delta for another year, Boeing doesn't sell a comparable product and Boeing's production is sold out for about eight years.

Boeing has petitioned the U.S. Commerce Department and the U.S. International Trade Commission to investigate subsidies for Bombardier's CSeries aircraft that it says have allowed the company to export planes at well below cost.

A preliminary determination on the petition is expected by June 12.

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