Industrial Disputes Act, 1947
(1) A strike or a lock-out shall be illegal if— (i) it is commenced or declared in contravention of section 22 or section 23; or (ii) it is continued in contravention of an order made under sub-section (3) of section 10 [or sub-section (4A) of section 10A]. (2) Where a strike or lock-out in pursuance of an industrial dispute has already commenced and is in existence at the time of the reference of the dispute to a Board, [an arbitrator, a] [Labour Court, Tribunal or National Tribunal], the continuance of such strike or lock-out shall not be deemed to be illegal, provided that such strike or lock-out was not at its commencement in contravention of the provisions of this Act or the continuance thereof was not prohibited under sub-section (3) of section 10 [or sub-section (4A) of section 10A]. (3) A lock-out declared in consequence of an illegal strike or a strike declared in consequence of an illegal lock-out shall not be deemed to be illegal.