How do you "enforce" an "intent?"
If you meant you think the LOI is still "IN FORCE," sorry, that LOI had an expiration date. It was extended to 12/31/2010 and never extended further.
"On September 27, 2010 RPC signed an extension of its original agreement dated July 13, 2010 to merge with Provista Diagnostics Inc., making the agreement between Provista Diagnostics and Radient Pharmaceuticals effective through December 31, 2010."
Besides, a LOI is not a legally binding contract that is ever "in force." It is an agreement that the parties intend to do something. At any time, either party can back out without paying a fine or getting sued.
Seriously though, the backdoor creeping merger rumor has, at its foundation, the 2010 LOI describing a merger between Radient and Provista? The Provista that had William Gartner as CEO? You don't think that Gartner leaving Provista might throw a wrench in this merger?