Mont. Code Ann. § 70-23-604

Labor performed or materials furnished with the consent or at the request of a unit owner or the owner's agent, contractor, or subcontractor may not be the basis for the filing of a construction lien against the unit of any other unit owner not consenting to or requesting the labor to be performed or the materials to be furnished, except that consent must be considered given by the owner of any unit in the case of emergency repairs performed or furnished with the consent or at the request of the manager.