KEY POINTS
  • The Signal app has nothing to do with a small company, Signal Advance, whose stock price multiplied 12-fold in two days.
  • Elon Musk suggested that his followers use the messaging app, but some people bought the unrelated stock.
  • Similar things have happened in the past to companies that have names similar to Zoom Video and Twitter.
Elon Musk, CEO of Tesla, stands on the construction site of the Tesla Gigafactory. In Grünheide near Berlin, September 3, 2020.

When Tesla CEO Elon Musk urged his Twitter followers on Thursday to "use Signal," he meant the encrypted messaging app. Some people appear to have taken it the wrong way.

Shares of an obscure and unrelated company called Signal Advance, which trades over the counter, surged 527% on Thursday and another 91% on Friday, climbing from 60 cents to $7.19.