Infinite & Lovelyz & Golden Child &Rocket Punch
All these groups are under Woollim Entertainment.
Zion.T & Somi
Both Zion.T and Somi are promoting under The Black Label.
Monsta X & Cosmic Girls (WJSN)
Starship Entertainment
Apink & Victon
Plan A Entertainment
BAP & SONAMOO & TRCNG
BAP members left the company, the other two hoobae groups are still under TS Entertainment.
BEAST & BTOB
Both ballad prince group debuted at Cube Entertainment. Beast members left the company and going on their way under the name of Highlight, BTOB are still under Cube Entertainment.
BLOCK B & ATEEZ
Block B debuted at Stardom Entertainment, but then had filed a suit against their agency and left the company. They moved on to the Seven Season company established for them in 2013. Seven Season founder launched another company called KQ to discover new talents. ATEEZ debuted as the first idol group of this new company called KQ.
MAMAMOO & ONEUS
RBW Entertainment
N.FLYING & SF9
FNC Entertainment
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You mention Beast (Who’s no longer under Cube) and BTOB. Yet you failed to mention CLC, Pentagon, (G)I-DLE who are currently under Cube. Heck if you’re talking about former label mates, you could’ve thrown in 4Minute too