Forbes: “A test case challenging the Internal Revenue Service (IRS) interpretation of expenses related to the sale of medical marijuana is headed to court: on Monday, June 6, Harborside Health Center, the country’s largest medical marijuana dispensary, will be in Tax Court to argue the application of section 280E of the Internal Revenue Code. Under current federal law, marijuana is classified as a Schedule I drug, putting it in the same category as heroin, . . . the IRS sent Harborside a bill for $2.4 million. The reason for the tax bill? The IRS declared Harborside (and thus all medical marijuana dispensaries) to be drug trafficking organizations (DTOs) and therefore subject to a special tax rule found at Section 280E of the tax code. That rule says that expenses connected with the sale of certain illegal drugs – including Schedule I drugs, like marijuana – are disallowed