Future Interest Subject To Defeat -- How -- Not Void

Mont. Code Ann. § 70-1-421, under Conditions and Limitations of Ownership.

Mont. Code Ann. § 70-1-421

A future interest may be defeated in any manner or by any act or means which the party creating such interest provided for or authorized in the creation thereof, nor is the future interest, thus liable to be defeated, to be on that ground adjudged void in its creation.