open shop

noun

1. a factory, office, or other business establishment in which a union, chosen by a majority of the employees, acts as representative of all the employees in making agreements with the employer, but in which union membership is not a condition of employment.

noun

1. an establishment in which persons are hired and employed irrespective of their membership or nonmembership of a trade unionCompare closed shop, union shop

A business that employs both unionized and nonunionized labor.