MedReleaf recently went public, becoming the largest North American pot stock IPO by market value of all time, while its competition has been busy expanding grow capacity in the wake of a growing number of medical cannabis customers and the expectation of recreational legalization. Canopy Growth Corp. acquired Mettrum Health earlier this year, widening its reach within Canada, and purchased 472,000 square feet of property, which also happens to house its headquarters. Meanwhile, Aurora Cannabis is working on a state-of-the-art 800,000 square foot facility known as Aurora Sky, and Aphria has moved onto its $100 million Phase IV expansion that’ll boost its grow capacity to one million square feet. These expansion figures sound great, if Canada moves forward with its recreational pot bill. If not, even with substantive growth in the medical cannabis market, there could be oversupply issues and weaker margins as a result. But this is far from the only problem. Health Canada also announced changes to its medical cannabis program in May that could have negative implications for the four Canadian marijuana stocks listed above. Health Canada plans to issue additional growing licenses, as well as allow existing producers to pack their vaults with supply, assuming it can be done safely and securely. In other words, it sounds as if extra competition and supply are on the verge of flooding the Canadian market. That’s not good news for any of these four companies.