Last year was supposed to be when marijuana stocks proved their worth to Wall Street by translating substantial sales growth into recurring profits. Unfortunately for these companies, and their investors, it didn't work out as planned. Supply issues throughout Canada and high tax rates in a number of legalized U.S. states dumped fuel on the fire that's allowed the black market to thrive. The end result was that pot stock investors were creamed.

At one point in 2019, more than $40 billion in market value had evaporated from the industry's highs. As we move headlong into 2020, the following marijuana stocks are what remain as the industry's largest.

A clear jar packed with cannabis buds that's lying atop a fanned pile of twenty dollar bills.

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1. Canopy Growth: $6.99 billion market cap

Consistent with the trend we've seen for a long time, Canopy Growth (NASDAQ:CGC) is the largest pot stock by a significant margin. At peak production, Canopy is likely the second-largest producer, and it has the second-broadest international reach, with a presence in 16 countries outside of Canada. The company's $2.1 billion in cash and short-term investments has certainly helped buoy its valuation in recent months, but steep ongoing losses and the hiring of a new CEO raise plenty of uncertainty surrounding the company's future.

2. GW Pharmaceuticals: $3.21 billion

Although its management team doesn't want to be lumped in with other "marijuana stocks," cannabinoid-focused drug developer GW Pharmaceuticals (NASDAQ:GWPH) has wiggled its way up to the No. 2 spot in market cap. Despite a rough 2019, GW Pharmaceuticals' leading cannabidiol-based oral drug, Epidiolex, has seen its net sales soar following its November 2018 launch. Having secured broad insurance coverage for Epidiolex, it's even possible that GW Pharma could become profitable on a recurring basis this year.

3. Curaleaf Holdings: $2.75 billion

Among U.S. vertically integrated multistate operators (MSO), none is larger than Curaleaf (OTC:CURLF). On a pro forma basis (i.e., assuming its pending acquisitions close), Curaleaf will have 131 retail licenses spanning 19 states. The acquisition of Select, as well as privately held MSO Grassroots, may even give Curaleaf a shot at $1 billion in annual sales this year, according to the company's management team. Look for the November elections to play a big role in drumming up investor interest in U.S. MSOs this year.

A gloved processor using scissors to trim a cannabis flower.

Image source: Getty Images.

4. Cronos Group: $2.33 billion

For much of the past year, Cronos Group (NASDAQ:CRON) has also found itself as a top-five pot stock by market cap. Although its production is nowhere near on par with its equally sized peers, and the company continues to lose money on an operating basis, it did receive a $1.8 billion equity investment from Altria Group in March 2019. With $1.53 billion in cash and short-term investments still on its balance sheet (as of the end of its most recent quarter), it's the second-most cash-rich pot stock in the industry, and is somewhat able to use its cash as a downside buffer.

5. Aurora Cannabis: $2.13 billion

Perhaps the biggest surprise is the absolute throttling Aurora Cannabis' (NASDAQ:ACB) valuation took last year. Between mid-March and year's end, Aurora shed more than $7 billion in market cap. Though it's the largest pot producer at peak capacity, and has a broader international presence than even Canopy Growth, the company's cash position appears insufficient to cover its many ongoing expansion projects. Furthermore, Aurora has racked up $3.17 billion Canadian in goodwill following more than a dozen acquisitions since Aug. 2016. This looks to be a massive writedown waiting to happen.

6. Green Thumb Industries: $1.89 billion

That's it! Just five cannabis stocks that are mid-caps. Every other weed company is a small-cap or micro-cap company, with U.S. MSO Green Thumb Industries (OTC:GTBIF) next in line. As of December, Green Thumb had 34 open Rise retail locations, as well as 96 total retail licenses across 12 states. This gives GTI, as the company is known, an addressable market of 151 million people in the United States. Green Thumb should have an especially active year with Illinois commencing adult-use sales on Jan. 1. GTI will look to open the maximum number of allowable stores (10) in the Land of Lincoln. 

Flowering cannabis plants growing under special lighting and vents.

Image source: Getty Images.

7. Tilray: $1.55 billion

Another perfect example of "how the mighty have fallen," is presented by Tilray (NASDAQ:TLRY). After listing its stock at $17 in its July 2018 initial public offering, and rallying to $300 on the dot by September 2018, Tilray has come full circle, and now sits at less than $16 a share. Management's de-emphasis on investing in the Canadian market has been a bit of a head-scratcher, as has been the company's regular purchases of wholesale marijuana. Tilray's late start to boosting production capacity has left it dependent on other growers to meet its own supply, thereby crushing its gross margin.

8. Aphria: $1.22 billion

Canada's third-largest grower by peak production potential, Aphria (NASDAQ:APHA), spent most of 2019 trying to regain investors' trust. That's because allegations of fraud, which were levied in December 2018 and mostly turned out to be false, did uncover conflicts of interest with some executives surrounding the company's purchase of Latin American assets. This led to the departure of longtime Aphria CEO Vic Neufeld. Thankfully, the purchase of pharmaceutical distribution business CC Pharma has somewhat counteracted these concerns by providing a steady stream of sales for Aphria.

9. Trulieve Cannabis: $1.18 billion

The last of the billion-dollar pot stocks is U.S. MSO Trulieve Cannabis (OTC:TCNNF). Unlike most MSOs, Trulieve has focused most of its attention on a single state: Florida. The company has opened 40 dispensaries in the Sunshine State, thereby keeping its costs close to the vest, and allowing it to effectively build up its brand. Trulieve's third-quarter report was truly a thing of beauty, with the company generating a no-nonsense operating profit of $23.6 million, if all one-time benefits and fair-value adjustments are removed from the equation. To date, it's the biggest true operating profit we've seen from a marijuana stock.

A large cannabis sign in front of a retail store.

Image source: Getty Images.

10. Harvest Health & Recreation: $0.93 billion

Lastly, there's U.S. MSO Harvest Health & Recreation (OTC:HRVSF), with a market cap of $930 million. Harvest Health has around 210 total licenses on a pro forma basis, with around 130 of those licenses giving it the right to open retail locations in 18 states. The company has a particularly robust presence in Arizona, which looks to be on the verge of legalizing adult-use cannabis in the Nov. 2020 elections. Harvest Health's key to rejoining the billion-dollar club will be whether the company can push into recurring profitability later this year.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.