Canada’s leading P3 toll road is fighting a tough legal battle to avoid repaying what could total more than Cdn $20 million in charges that may have been improperly collected from customers who went bankrupt.

The company distributed a dividend of C$680 million to all shareholders in 2013, so the potential loss is not a big concern now. But the very long term of its concession makes any abridgement of its right to collect tolls a top priority.