Constellation Brands Inc. shares rallied Thursday, after Canadian cannabis company Canopy Growth Corp. announced a deal that will give it the rights to acquire U.S. multistate operator Acreage Holdings Inc. as soon as the U.S. federal ban on cannabis has been lifted. The deal brings changes to the terms of Constellation's warrants in Canopy, in which it has invested $4 billion, according to Wells Fargo analyst Bonnie Herzog. As part of that deal announced last August, Constellation Brands gained 38% ownership and received warrants that if exercised would raise that stake to above 50%. Herzog wrote in a note to clients that there are four key impacts from the modification of the warrants, three of which are positive and one slightly negative. On the positive side, the deal extends the exercise period for Constellation to five to eight years from three years previously, "suggesting less 'cash out the door'," for the Corona beer distributor. Also positive, the deal does not change Constellation's representation on the Canopy board in the form of four directors. The deal splits the Tranche B warrants into two parts, "75% of total will be exercisable at C$76.68 ($57.31)with the remainder kept at VWAP (volme weighted average price) - High exercise price (vs where CGC is currently trading at C$57.11) reflects STZ's strong confidence in its CGC investment," Herzog wrote. The slight negative is that the deal now caps Constellation's ownership at 50%, she said. "Net/net - We view today's announcement as positive and continue to believe STZ's involvement in cannabis/CGC positions them well to take a leading position in the global alcohol/cannabis industry over the next decade plus," said the analyst. Constellation shares were up 3.6%, and have gained 18% in the last 12 months, while the S&P 500 has gained 7%.