Cannabis stocks were mostly sharply higher Monday, with India Globalization Capital Inc. a standout, adding another 18% on excitement about its plans for the CBD-infused-energy-drink market.

Maryland-based India Globalization’s stock IGC, +26.61% gained 27% on Friday after it revealed the plans, pulling the stocks of other companies already involved with the cannabinoid higher with it.

The overall cannabis sector has been on a tear for the past few months as investors position themselves for the start of full legalization of cannabis in Canada on Oct. 17, the first developed country to take that step.

Canadian companies have been gearing up for the move — and posting outsize stock gains — and newswires have been flush with announcements of deals, alliances, production and supply agreements and emerging companies, keen to take advantage of what is expected to be a multibillion-dollar market.

But in all the euphoria, investors, and retail investors in particular, need to do their due diligence to be sure the companies they are investing in have legitimate businesses. The Securities and Exchange Commission has issued an investor alert warning that promises of guaranteed high returns on investments are a red flag for fraud.

“Fraudsters may manipulate stock prices (for example, causing them to rise or fall dramatically) by spreading false and misleading information about a company,” it reads. “Microcap stocks, some of which are penny stocks and/or nanocap stocks, may be more susceptible to market manipulation than stocks of larger companies.”

Investors have become increasingly keen on CBD, a nonpsychoactive component of marijuana, that is being used in drinks and beverages as a health boost. The beer industry has proved especially interested, given the growing evidence that people are using cannabis to replace alcohol, while big soda companies are turning to CBD to build out their wellness offerings at a time when consumers are avoiding sugar.

The Drug Enforcement Administration said last week that it now places FDA-approved drugs with CBD in “Schedule V,” defined as having the lowest potential for abuse, such as over-the-counter treatments for diarrhea and cough suppressants. Cannabis itself remains a Schedule I drug, which places it alongside heroin and LSD as substances that are fully banned at the federal level. That classification has hampered the development of the U.S. sector as companies are unable to have bank accounts that are federally insured, handing Canada a valuable first-mover advantage.

The Toronto-based Green Organic Dutchman Holdings Inc. said Monday it has entered a C$75 million deal with an underwriting syndicate led by Canaccord. Proceeds of the deal are to be used to finance international expansion and for the catchall general corporate purposes.

Shares of Canada’s Tilray Inc. TLRY, +3.65% surged another 13% Monday, bringing its one-month gains to 149%. Other Canadian stocks were also higher, with Aurora Cannabis Inc. ACBFF, +1.07%ACB, +0.40% up 3%, Canopy Growth Corp. CGC, +0.43% up 3%, Valens GroWorks Corp. MYMSF, +1.47% up 3.7%, Cronos Group Inc.CRON, +1.80% up 5.8% and iAnthus Capital Holdings Inc.ITHUF, +0.89% up 5%.

Aleafia Health Inc. stock’s ALEF, -1.29% slid 1.9%, as investors took profits on last week’s 27% gain. The company said it is planning to expand into retail operations and entered a supply agreement with CannTrust Holdings Inc. TRST, -2.05% , which was also down about 2%.

Among U.S. stocks, New Age Beverages Corp. NBEV, +2.91% , another CBD drinks player, soared another 38%, adding to gains that have totaled 395% in the past month. That company is planning to debut a line of CBD-infused drinks at the North American Convenience Store show in Las Vegas on Oct. 8.

Rival Level Brands Inc. LEVB, +23.21% , which is offering CBD drinks under the Kathy Ireland Health and Wellness brand, rose another 38%.

Cannabis Sativa Inc. CBDS, +29.20% was up 10% and GrowGeneration Corp. GRWG, +2.79% was down 2%. GW Pharmaceuticals PLC’s stockGWPH, -3.17% which makes the only FDA-approved, CBD-derived drug, Epidiolex for the treatment of pediatric epilepsy, was down about 2%.

The ETFMG Alternative Harvest ETF MJ, +1.77% was up 3% and the Horizons Marijuana Life Sciences ETF HMMJ, +0.90% was up 2%. The S&P 500 SPX, +0.36% was up 0.7%, and the Dow Jones Industrial Average DJIA, +0.73% was up 1%.