I don't think there is a "german steel" per se. I suppose the "Solingen" formulas may be somewhat similar, but each is proprietary to the maker, I suspect (to the extent there is truly a difference in the makers; I understand that there has been some consolidation in the German industry such that some of the old names are made side-by-side in the same factory).
A relatively common feature of Solingen pocket knives used to be that the blades were forged (not like an ABS blade, but hot-punched from stock and beat on a few times before stock removal), which could result in a better blade than more common cold punching or sawing/laser/water cutting of blanks. I'm not sure many makers carry this on, but I think Carl Schlieper/Eye Brand continues to state that blades are "hammer forged."
The consensus is that the carbon steel used in German knives is fairly similar to 1095, while the stainless, as usual, is more like 440A or 420HC. Puma used to make some wicked-hard stainless that is believed to have been 440C or similar.