Google translate:
Silvermax corresponds to an APX 100 formulation with slightly finer grain, slightly lower sensitivity and higher silver application
The usual semi-vague language "
corresponds to an APX 100 formulation", enough to feed hopes, and create "internet facts" that will gain further "truth" as they are repeated across forums.
Robert Vonk, manager of Fotohuis, has professional contacts with the actual suppliers of film, and should know better. See his post in:
http://photo.net/black-and-white-photo-film-processing-forum/00bCFH
and his other post in:
http://www.l-camera-forum.com/topic/187474-adox-silvermax/page-3#entry2122362
See in that thread the reaction of some forum members in disbelief of the simple truth.
The same kind of commercial language, crafted to feed the hopes (and purchases) of enthusiasts, exists around so-called "Rollei" films, rebranded stock from various origins (Kentmere, Agfa Aviphot, etc...).