I recently read a post (can't remember where) from someone with a similar problem. Their lender's EQ and EX scores matched the Classic FICO scores from MyFico, but the TU didn't. It turned out that the trimerge report provided to the lender by the third-party reseller included a TU FICO (Empirica) based on the 1998 model. I believe (Tuscani or someone can correct me if I'm wrong) that the TU FICO from MyFico is the more recent version (Empirica 2004). So that's one possibility, although 50 points sounds like an awfully big difference for two version dates of the same scoring model. You might ask the lender if they can give you any specific scoring model information from the trimerge report.