SK3 Group Inc. (SKTO)

[DarthYoda]

Here is some info, it is a little outdated with the number of states, but the overall situation is the same:

Medical marijuana: Treatment of deductions for expenses in business legalized under state laws[edit]

Recently, the provisions of Internal Revenue Code section 280E are being applied by the Internal Revenue Service (IRS) to businesses operating in the medical marijuana industry. Section 280E provides:
No deduction or credit shall be allowed for any amount paid or incurred during the taxable year in carrying on any trade or business if such trade or business (or the activities which comprise such trade or business) consists of trafficking in controlled substances (within the meaning of schedule I and II of the Controlled Substances Act) which is prohibited by Federal law or the law of any State in which such trade or business is conducted.
Even though 18 states have medical marijuana laws (and two of those states now allow marijuana to be consumed without a doctor recommendation), the IRS is applying section 280E to deny business deductions. Businesses operating legally under state law argue that section 280E should not be applied because Congress did not intend the law to apply to businesses that are legal under state law. The IRS asserts that it was the intent of Congress to apply the provision to anyone "trafficking" in a controlled substance, as defined under federal law (as stated in the text of the statute). Thus, section 280E is at the center of the conflict between federal and state laws with respect to medical marijuana.[22][23]

http://en.wikipedia.org/wiki/Taxation_of_illegal_income_in_the_United_States#Medical_marijuana:_Treatment_of_deductions_for_expenses_in_business_legalized_under_state_laws