Mont. Code Ann. § 7-14-2827

The bond required of the owner or keeper of the ferry must be in the sum fixed by the board of county commissioners, with one or more sureties, and conditioned that the ferry will be kept in good repair and condition and that the owner or keeper will faithfully comply with the laws of the state and all legal orders of the board regulating the ferry and pay all damages recovered against the owner or keeper by any person injured or damaged by reason of delay at or defect in the ferry or in any manner resulting from a noncompliance with the laws or lawful orders regulating the ferry. The bond must be approved by the board.