The upstart NEO Exchange scored its first billion-dollar corporate listing today with U.S. medical cannabis producer Columbia Care.

The New-York based cultivator, manufacturer and dispensary operator made its debut with a market capitalization of more than $2-billion.

The stock exchange said Monday the multi-state operator, with a presence in roughly 15 states, is the first company to list on the NEO with an enterprise value of over $1 billion.

"This is an exciting time to be partnering with a leader in the U.S. cannabis sector as it moves into its next phase and looks to raise capital on the North American public markets," NEO chief executive Jos Schmitt said in a statement.

Columbia Care trades under the symbol CCHW.

The listing marked a milestone for the NEO Exchange, which launched in mid-2015 and whose owners and investors include BCE Inc. and the OMERS pension plan.

The NEO said it now represents close to 10 per cent of all volume traded in Canadian-listed securities, including a growing number of cannabis-industry companies.

Columbia Care's vice-chairman and chief executive Nicholas Vita said in a statement that it looks forward to "leveraging the benefits afforded to us by being listed on the NEO exchange as we look to accelerate the growth of our company."

U.S. cannabis companies have been flocking to Canada to raise public capital because they are restricted from doing so at home, as pot remains illegal federally south of the border. Cannabis for medical or recreational purposes has been legalized in several states, but it is considered to be a Schedule 1 drug.

Canada's largest exchange operator TMX Group -- which operates the Toronto Stock Exchange and the TSX Venture exchange -- warned in 2017 that listed pot companies with assets in the U.S. were not in compliance with their requirements and could face delisting.

That sent many U.S. cannabis companies over to the Canadian Securities Exchange, which allows these firms to list provided they disclose the associated risks to investors. Last year, cannabis and related companies accounted for 60.5 per cent of the trading volume on the CSE, it said.

Meanwhile, the U.S. political climate is becoming more receptive to cannabis, with legislation potentially opening the door to the massive market. Earlier this month, the bipartisan STATES ACT -- legislation that would amend the Controlled Substances Act and could effectively make cannabis federally legal in states where recreational consumption is legal -- was reintroduced in Congress.

The U.S. market including illicit sales is estimated be worth between US$35 billion to US$50 billion, or roughly 10 times the size of Canada's market, according to a Piper Jaffray & Co. analyst.