for the record: SKF is not Swiss but Swedish, and credited with inventing (and patenting) the sealed cartridge bearing back in 1907 (!) or at least I've seen examples that look exactly like the current cartridge bearings that date from the early '20s. So it would make sense that SKF would have supplied the bearings to any/all of the European BB manufacturers, but as to whether they made the entire unit(s) I can't be sure. At least some of the features of the Mavic, for example, were exclusive.
I think both sealed and open BBs have their benefits and their detriments. I use both. The verdict is still out for those new-fangled wide-mouth BBs with tiny sealed ring bearings (GXP, UT, Hollowtech II, etc.), but I bet they don't hold up for the long haul.