Last January, TransCanada said it had secured shipping commitments totalling roughly 500,000 barrels a day on the line, including a deal with the Alberta government to ship 50,000 barrels a day of provincially owned crude.
Other Keystone XL shippers include major Calgary-based oilsands producers Canadian Natural Resources Ltd., Suncor Energy Inc. and Cenovus Energy Inc.
The 1,897-kilometre pipeline would carry as much as 830,000 barrels of crude per day from Hardisty, Alta., to Steel City, Neb., and on through a half dozen states to refineries on the Gulf Coast.
Becky Mitchell, chairwoman of the Northern Plains Resource Council, a plaintiff in the Montana legal action against Keystone XL, said her environmental organization is thrilled with the ruling.
The company and opponents of the project have been in a decade-long dispute that has spanned several presidencies and involved standoffs between protesters and law enforcement.
In 2008, the U.S. State Department issued a presidential permit for the pipeline and TransCanada filed paperwork to expand the project. After years of legal wrangling, Barack Obama rejected the permit in 2015.
The company responded by seeking $15 billion in damages. Trump signed executive actions to again advance construction of the project in 2017.