Potash Corp, page-28

Companies go into joint ventures all the time, no biggie. They're still separate companies.
Half the projects on the north west shelf in oz for a recent example. Apache energy sells out their portion of a joint venture project and Woodside or others pick it up, also companies get bought out and the buyer assumes JV responsibility, all normal.
Don't listen to half the krap on hot copper from people who have very limited corporate or business understanding or experience.

You know why you invested, back yourself and place on ignore the posters who have no idea what they're on about. You wouldn't listen to fools on the street, why is a share forum any different?
Best thing you did was contact the company directly.