So, to the best of my knowledge, and experience, the rectangular clear and white sticker was used by SNK on, if not all, most of the soft case games up until those cases were dropped in 1995 with the release of Fatal Fury 3. A few snap-lock games over 1995 continued to use the soft case seal, but by the end of the year SNK had moved to using a small black circular sticker with the neo-geo logo on it.
Now, that's not to say that SNK may have continued to randomly apply whatever left over stock of clear sealing stickers they had - especially as they were inconsistent as fuck with just about everything - but my general rule of thumb is by 1996 the practice had ended.
I think by 1998 they just stopped using sealing stickers period.
If anyone here knows different it would either by
@Shito or
@massimiliano .