Similarly, the close interrelationship between contractors and subcontractors in the clothing and apparel industry present unique problems for the enforcement of union standards in the industry. Unions may negotiate struck work clauses, but only to the extent that the workers would have the right to strike in support of another unit. Agreements which restrict the handling of products in the normal course of the employer's business are unlawful. I f a union has a struck work clause limited to work which would not have been done but for the existence of a labor dispute, the clause is valid. The union, therefore, has the right to negotiate language limiting the ability of its primary employer to act as an ally of another struck employer.
Similar restrictions apply to contract clauses giving workers the right to honor a picket line.
Such a clause cannot give to workers the right to honor a secondary picket line. Valid picket line clauses must be limited to the right to honor legal, primary picket lines. Work Preservation or Insourcing Issues Agreements which attempt to expand the jurisdiction of the union to work which has previously been done by another employer are technically hot cargo agreements. Work preservation clauses are generally legal. An agreement bringing work back to a bargaining unit would be a valid effort to reclaim lost work, even though an effect would be to cut off the business relationship between the primary employer and the company which had also done the work .