Which two ridings do they have a deal [qm]
Central Nova and Saint-Laurent-Cartierville. In the former, no Liberal candidate is opposing May. In Dion's riding, there's no Greenie.
I also read somewhere that the Tories aren't running a candidate against Independent Andre Arthur in Portneuf—Jacques-Cartier. They don't want to risk splitting the federalist vote, or so the story goes.
The Greens are also, as mentioned earlier, not running a candidate against Bill Casey (basically so May can hammer MacKay on the Atlantic Accord).
Wait! Did the Greens make an agreement with any party? In countries like Chile, the Concertación and the Juntos Podemos just reached an agreement for this year's township elections to have one alliance not run a candidate against the other one if the partner alliance does the same.