KEY POINTS
  • Citron’s Andrew Left says he’s long on Lyft and is buying more shares in the open market. To bet against it is an “amateur trade,” he says.
  • The ride-hailing company debuted on the Nasdaq last week, and share prices have been volatile since.
  • “Shorting disruptive companies that dominate a megatrend simply because they lose money is a sure way to go broke,” Left says.
Signage for Lyft is seen displayed at the NASDAQ MarketSite in Times Square in celebration of its initial public offering (IPO) on the NASDAQ Stock Market in New York, U.S., March 29, 2019.

One of Wall Street's most prominent short sellers has a word to the wise: Don't bet against Lyft.

Andrew Left of Citron Research -- famous for shorting Tesla and Valeant Pharmaceuticals -- called betting against the ride-hailing company an "amateur trade."