The head of a medical marijuana advocacy group says many of Montana's 471 registered providers will have to shut down after a court upheld most of the rollbacks of the state's medical pot law.

Montana Cannabis Information Association President Mort Reid said Friday he is advising providers to comply with the Montana Supreme Court's ruling within two weeks.

On Thursday, the court ruled that providers can sell marijuana to no more than three registered users each. It upheld other restrictions passed by state lawmakers in 2011 to review doctors who recommend the drug to more than 25 patients in a year and ban pot advertising.

Supreme Court clerk Ed Smith says the ruling does not take effect until the judgment is formally entered in district court, which won't happen before March 10.

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