It took Andrew Left, pundit and short seller, a seven-minute video to steamroll one of the most promising e-commerce stocks on the market. He declared that Shopify, Inc. (SHOP) , the celebrated online retailer, would be offline in two weeks, voicing concerns about its customer base. But analysts, consultants and Shopify users told TheStreet that Left's rant didn't hold much water.

Shopify, a Canadian e-commerce company that offers small businesses an online platform to market their wares, could be lying about the size of its customer base and promoting itself as a "get rich quick" opportunity, Left suggested on Wednesday on his website, Citron Research. He also likened the company to Herbalife Ltd. (HLF) , a controversial multilevel marketing company that was fined $200 million by the Federal Trade Commission earlier this year for an alleged pyramid scheme.

"Shopify says they have 2,500 Shoplift plus merchants out of their universe of 500,000," Left said in his YouTube video. "Now let's say they have another 20,000 Shopify Advanced. The question I ask you, the question no one on Wall Street has addressed, is who are the other 450,000 merchants on Shopify?"

In an interview with CNBC Wednesday, Left said he had already shorted Shopify stock. Following Left's explosive indictment, Shopify saw its shares tumble 9% in less than a day.

Analysts, consultants and Shopify users TheStreet spoke to Wednesday, Oct. 4—both on and off the record—expressed skepticism about Left's claims and motives.

Given the complex ecosystem in which Shopify operates - it deals with a whole host of vendors and payment processors - it would be very difficult for the company to create an enduring myth about the size of its customer base, experts said. The project manager for a New York City-based creative agency that partners with Shopify, for one, said that he had not heard any talk among Shopify users about "an inflation in user base."

"Having worked 15 years in this field, I think Shopify has a pretty solid product, and it's one that clients are happy with," said the manager, who spoke to TheStreet on condition of anonymity. He added that most of Shopify's users are small and very small merchants that may not have much of a footprint.

Shopify stands behind its operation and service to customers, a company spokeswoman told TheStreet in an email statement Thursday, Oct. 5. Stores using Shopify's platform generated $10.7 billion in gross merchandise volume in the first half of 2017, according to the company.

"We vigorously defend our business model and stand resolutely behind our mission and the success of our merchants," the company said. "A LOT (sic) of people buy from stores that use Shopify: over 131 million consumers have bought from a store using Shopify in the last 12 months."

Other analysts said Left's claims weren't grounded in reality.

"The way that he is spinning it is unfair and incorrect," said Tom Forte, an analyst at D.A. Davidson Companies, who follows the stock. "It's laughable-all smoke and no fire."

Bard Equity's Colin Sebastian called Left's critique a "buying opportunity."

"We view the comparison with Herbalife as clearly misleading, as Shopify is not a multilevel marketing company," he wrote in a note Wednesday. He deemed Left's short report is "offbase."

Left could not be reached for comment. This isn't the first time he has come out as a crusader against a stock. He made his reputation with his campaign accusing Valeant Pharmaceuticals International, Inc. (VRX) of "price-gouging." The FTC later investigated the company.

Earlier this year, Left took on cancer-testing company Exact Sciences Corp.  (EXAS) , declaring its colon cancer testing product is overpriced and provoking the firm's CEO Kevin Conroy in a shouting match on CNBC.

Left's claims could have an impact beyond Shopify's plunging shares. If valid, they could catalyze a Securities and Exchange Commission investigation or a shareholder lawsuit, said Anthony Sabino, a securities attorney and law professor at St. John's University.

"There's no proof that Shopify has misrepresented anything," Sabino said. "If he's spreading information maliciously because he wants to solidify his short position, that is market manipulation - securities fraud. But if he has honestly come to this decision, he's at liberty to express his opinions."

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