I just happened to come across a case which is an example of this type of litigation: Hydro-Electric Power Commission of Ontario v. The Coniagas Reduction Company, Limited, [1933] UKPC 44, on appeal from the Ontario Supreme Court to the Judicial Committee of the Privy Council in London.
At issue was an agreement between two companies that apparently had a good working relationship, but they could not determine if the agreement (which they had inherited from their predecessors) was perpetual in nature. So they went to court:
There must have been a lot of money at stake, to take it all the way to the JCPC.