I did a brief search and didn't find much in the way of efficiency ratings for MANN filters. I'd wager it's about the same as a Purolator Classic, though. Just from seeing the type of element from cut open/side-by-side pictures.
Granted, that doesn't guarantee media properties, but more of a gut conclusion given the limited information they give about their filters. At least, in the NA region. Maybe in Germany they have all kinds of info.
Here are some older BITOG threads. A couple show they probably have ratings at larger micron. Though one claims 9 micron
?!
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=929689
That was from a 'forwarded' US sales person email with a returned German answer wrt efficiency of a particular MANN filter p/n.
Just go to AAP, search mann, ignore vehicle spec and look at them filter at a time. The spin-ons don't seem to have efficiency spec but the cartridges are listed generally around 99% @ 40micron.
Case in point, this cartridge has a 99% efficiency at? 38.7 micron. .7 of a micron to get that efficiency of 99% as desired I guess.
http://shop.advanceautoparts.com/p/mann-...mann#fragment-2
Others varry, result 2 has a cartridge of 99% but at 38 micron. I think they just show w/e micron they achieve 99% efficiency at at least wrt their cartridge.
Perfectly in line with a Puro rated at 97.5% at 25micron, eh?