With Canada legalizing marijuana nationwide in October and several states already having legalized it, there’s a lot of money to be made in the marijuana market.

Numerous notable US investors have taken notice and begun investing in the industry as a result.

Leon Cooperman, a 75-year-old hedge fund businessman and billionaire, recently shared his interest in these investments, asking questions during an earnings call with Green Thumb Industries. He also revealed he has made a small investment in the company, although he credits that choice to the fact he is personal friends with the father of the company CEO and the CEO himself.

Meanwhile, Marcato Capital Management is playing cards close to the vest. However, an August filing by fund head Mick McGuire reported a 2% investment in Green Thumb, purely for investment rather than control purposes per McGuire.

In the US, current investment options are limited for the average investor. as they need to invest directly in a marijuana business, which requires a large amount of capital and access to these businesses.

Federal regulations are also a sticking point, as marijuana is still a Schedule I regulated substance. Therefore, companies involved in the growth and sale of cannabis cannot go public, preventing trades on the stock market itself.

Considering the fact that Canada is moving toward legalization in mid-October, there may be a working model for the US to follow for legalization.

In the meantime, states need to clarify their legislation to protect businesses and consumers when it comes to investing and allowing access to financial services. This will benefit the companies working to grow and expand in the marijuana industry, since they currently have little or no access to credit lines or financing options beyond actual currency.

The projected estimate for the medical marijuana industry is an increase from the $4.7 billion in 2016 to a market value of $13.3 billion in 2020. This is a significant reason for efforts to change legislation in the coming years.