A split file occurs when you have so much data in your file --old accounts, new accounts, hard inqs, soft inqs, you name it --that the software can no longer keep all the information in one electronic file. Some of the excess spills over or splits to form a parallel file. If it's accounts that split off, you can get two wildly varying scores, depending on which portion of the file is pulled for scoring.
Whenever I read where someone's EQ score suddenly went up 53 points, then down 53 points, then up 53 points (insert your own number), I think split. It sometimes happens on TU, but it mainly happens on EQ. It's a good idea to print out one of your full reports. If you file ever splits, fax your older report to EQ (obviously you call them first), and they can re-build your file.
EX seems to have rock-solid, stable software, where everything pretty well stays put, and I'm convinced that's why you see so many of the "prime" CCC's pulling EX. I'll bet they charge prime for it too, so as EQ and TU get their software issues under control, they're going to doing some serious marketing among lenders.
* Credit is a wonderful servant, but a terrible master. * Who's the boss --you or your credit?
FICO's: EQ 781 - TU 793 - EX 779 (from PSECU) - Done credit hunting; having fun with credit gardening. - EQ 590 on 5/14/2007