They are using a "Simmons Consumer Segmentation Systems" of experian (marketing services), so it seems.
(a) mosaicCd is a direct mosaic definition product of experian
http://www.experian.com/assets/marke...c-brochure.pdf
and
(b) mindsetSeg (mindset segmentation) is a product that seems to be more customized product for DL out of a customized research (maybe "Simmons Integrated Marketing Solutions" or "Simmons Custom 360"-based solution?). I assume that the two letter system marks customer profile on two main market/target areas for which DL has an interest (e.g. spending and preferences).
Furthermore, DL does purchase from experian additional online and business analytics services (e.g.
http://www.experian.com/hitwise/delt...ase-study.html ), so it makes sense that they would want to use an integrated product setting.
We can make guesses or explore more. I think there are some marketing analysts on FT.