To put it as simply as possible: Thorner had some patents that both Sony and Immersion tried to get during their legal squabbling. Thinking it might net him some cash, Thorner licensed his patents to Immersion, which won its case against Sony. Immersion then went after PDP/Electro Source, which also licensed Thorner's patents after he believed his deal with Immersion expired. But (stick with us!) Sony and PDP/Electro Source had teamed up, and Thorner alleges that he wasn't informed of the deal, which made him license his patents to PDP for much less than he could have had he known (that's the "tricked him out of cash" part).
God, that was exhausting. If you want even more detail (if not necessarily a better understanding) of the case you can read GamePolitics' full piece here.
Sony PlayStation 2 1st-gen
Sony PlayStation 3 (late 2012)