It's an inside pass with plenty of room, so I would give it:
A.) Beginner group? - Dangerous, beginners are already nervous about being on the track, while the pass itself wasn't dangerous, it could spook someone new to the track when someone suddenly comes into the path they were going to take. Granted, the act itself is not dangerous per say, but the reaction it could cause is.
B.) Intermediate group? - OK. Try not to pass on the inside in intermediate, but if you do, give plenty of room, like you did. I wouldn't bust your balls on it for intermediate, but if you asked me for my opinion, I would probably suggest waiting to pass on a straight or outside of turn.
C.) Advanced group? - Not even worth mentioning. I would consider anything fair game in advanced group as long as it wasn't directly aggressive to the other rider such as stuffing them off the track or something like that.
D.) Racing? - Hell, I've actually bumped into people in turns in racing, it's all fair game as long as it's not trying to kill someone.
WERA Expert #43
2012 WERA National Challenge Series Open Superstock Novice Champion
COMET RACING LEATHERS
2011 ZX-10R Race bike (Vortex, Silkolene, Leatt, Yoshimura, BRIDGESTONE)
2013 ZX-6R 636 Race bike
2008 Ducati Hypermotard 1100s