law: Industrial Disputes Act, 1947
  18.Persons on whom settlements and
  
  awards are binding
   104  [(1) A settlement arrived at by agreement between the
  
  employer and workman otherwise than in the course of conciliation proceeding
  
  shall be binding on the parties to the agreement.
  (2) 105[Subject to the provisions of sub-section (3),
  
  an arbitration award] which has become enforceable shall be binding on the
  
  parties to the agreement who referred the dispute to arbitration.]
   106  [(3)] A settlement arrived at in the course of
  
  conciliation proceedings under this Act 107[or an arbitration award
  
  in a case where a notification has been issued under sub-section (3A) of
  
  section 10A] or 108[an award 109[of a  Labor Court , Tribunal or National
  
  Tribunal] which has become enforceable] shall be binding on-
  (a) all parties to the industrial dispute;
  (b) all other parties summoned to appear in
  
  the proceedings as parties to the dispute, unless the Board 107[arbitrator]
  
  109[Labor Court , Tribunal or National
  
  Tribunal,] as the case may be, records the opinion that they were so summoned
  
  without proper cause;
  (c) where a party referred to in clause (a) or
  
  clause (b) is an employer, his heirs, successors or assigns in respect of the
  
  establishment to which the dispute relates;
  (d)where a party referred to in clause (a) or
  
  clause (b) is composed of workmen, all persons who were employed in the
  
  establishment or part of the establishment., as the case may be, to which the
  
  dispute relates on the date of the dispute and all persons who subsequently
  
  become employed in that establishment or part.