Semb Marine plunged but Semb Corp closed at day high?

Logically, Semb Corp should drop and can't be closing at day high.

 

Closing price is normally done by the Pros.

 

 

Is Semb Corp doing buy-back?

 

Or may be some people switching out from Semb Marine to Semb Corp to maintain some exposure to Semb Marine while hoping for special dividend from Semb Corp???