What would be the Federal Business Code/NAICS code # for a limited liability limited partnership (LLLP) managing mineral rights?
Okay, I believe I found the NAICS code number I need to file Montana Tax Return. The North American Industry Classification System (NAICS) at census.gov lists "Oil Royalty Companies" or "Oil Royalty Leasing Companies" as 533110.
It turns out that if you have formed an entity to handle your Montana mineral rights and you have registered the entity with the Montana Secretary of State, you must file a Montana Tax Return even if you have "NO - ZERO" income. I am filing our delinquent 2012 tax return because we have been threatened with a $10 penalty per partner and we have 40 partners. :-)