Cannabis producers have issued stock worth this amount in the first five weeks of 2021, investment firm Viridian Capital Advisors estimates, as prices have risen on a promise of federal decriminalization of marijuana and a host of other reforms by the incoming Biden administration.

Canadian pot companies have been the largest beneficiaries of the rally in shares, owing to the fact that they have been allowed to list on U.S. exchanges, while U.S. companies that harvest or sell marijuana within the country are forbidden from doing so.

Retail investors have also piled into the pot sector this week, with Tilray, Aphria and Sundial Growers emerging as the new favorites of Reddit's popular WallStreetBets forum that was behind recent rallies in some shorted stocks.

(Graphic: Cannabis stocks rally to new highs: https://graphics.reuters.com/CANNABIS-STOCKS/xlbvgymnxvq/chart.png)

In a vote of confidence in the sector, a single unnamed institutional investor this week bought $100 million worth of stock in U.S.-based pot producer Green Thumbs Industries Inc's initial public offering, according to a company filing.

Calgary, Alberta-based Sundial, a medical cannabis producer, has issued over a billion new shares since September.

Considered by many analysts to be a bankruptcy risk earlier, the company has improved its cash position from $22 million to over $600 million in just four months and fully repaid its current debt obligations.

(Graphic: Pot producers raising record money: https://graphics.reuters.com/CANNABIS-STOCKS/FUNDRAISING/xklvyozegvg/chart.png)

Market experts, however, have said the cannabis rally is already overdone and valuations are once again becoming unrealistic, especially for the Canadian companies that may not even get much upside from U.S. decriminalization.

Viridian said the turnaround in Sundial's fortunes is good for them, but the advisory firm is "a bit skeptical about any fundamental changes at the company justifying this Cinderella story".

AMC Entertainment and American Airlines were among a handful of companies to have raised funds from the market when their shares soared last month.

GameStop could not seize on the Reddit-fueled rally to sell shares because of regulatory restrictions, according to three people familiar with the matter.

(Reporting by Shariq Khan in Bengaluru; Editing by Alex Smith and Saumyadeb Chakrabarty)

By Shariq Khan