The Supreme Court won't hear an appeal challenging a Montana law that limits medical marijuana providers to selling the drug to a maximum of three patients each.

The justices on Monday let stand a Montana Supreme Court ruling that upheld key provisions of a state law that rolled back much of the 2004 voter-approved initiative legalizing medicinal marijuana.

The Montana Cannabis Industry Association said the rollbacks would force the closure of dispensaries and leave patients without a legal way to obtain the drug.

The new restrictions are set to take effect Aug. 31.