§ 1381. Withdrawal liability established; criteria and definitions
(a)
If an employer withdraws from a multiemployer plan in a complete withdrawal or a partial withdrawal, then the employer is liable to the plan in the amount determined under this part to be the withdrawal liability.
(b)
For purposes of subsection (a) of this section—
               	 	
               	 	
(1)
The withdrawal liability of an employer to a plan is the amount determined under section 
1391 of this title to be the allocable amount of unfunded vested benefits, adjusted—
(2)
The term “complete withdrawal” means a complete withdrawal described in section 
1383 of this title.
(3)
The term “partial withdrawal” means a partial withdrawal described in section 
1385 of this title.