key word you used was 'vendor.'
While I don't know the specifics of MMJ transactions re: the state (and I am not an attorney) I have been in business for over 27 years, and know the tax laws pretty well. If you sell something, you must report it to the BOE. If I was going to sell my MMJ to a storefront, the way I would list it on my Sales Tax report would be that it's a wholesale transaction (meaning that the person I am selling it to would resell it.) As a 'Wholesaler' you do not pay sales tax to the state, because you are not collecting sales tax from the business you are selling your product to. The entity that sells to the end user is the entity that collects the sales tax and then reports that to the state as a retail sale.
You still must list all non-taxable transactions. You will have to have 'on file' the resale # of the entity you are selling to, as this helps prove that you were the 'wholesaler.'
This is all from my personal experience in the manufacturing industry ( and it's not weed that I manufacture.) That's my disclaimer that the same rules MAY not apply.
IMHO I would not file with the State unless the dispensary you sell to requires you to have a business liscense, which in turn means you would have to file with the BOE as well.
Would love it if someone with more direct experience would speak to this.
