The Colorado Senate gave preliminary approval on Wednesday to a bill that would open up the industry to new investors -- including those from out of the state.

Only Colorado residents can invest in pot stores, grows and edible makers right now. The current restrictions on investment were put in place, in part, to limit the growth of the industry, and make regulating ownership easier.  But that also means a roadblock to expansion. 

Under the bill, individuals, banks and pension funds from anywhere in the U.S. could own a piece of the fledgling industry -- with two big exceptions: publicly traded companies and international investors.

The bill has another vote in the state Senate, then it’s on to the House.