Elon Musk said ‘use Signal’ and confused investors sent the wrong stock up 438% on Monday

Four days after Tesla CEO Elon Musk prompted Twitter followers to “use Signal,” a reference to the Signal encrypted messaging app funded by a nonprofit organization, investors pushed even higher the price of Signal Advance, a small component manufacturer whose stock trades over the counter.

During Monday’s trading session, the stock rose 438% and reached a high of $70.85, up from a closing price of 60 cents on Jan. 6, a day before Musk’s tweet. The stock saw its highest trading volume since going public in 2014 on Monday; more than 2 million shares changed hands, while on Jan. 4, not a single share of the stock was traded. Signal Advance, which reported receiving no revenue in 2015 and 2016, is now worth more than $3 billion.

The buying fever that began soon after Musk’s remark illustrates an occasional issue in public markets of people investing in the wrong companies by mistake.

A similar case played out in 2019 as some people bought shares of Zoom Technologies, whose ticker symbol was ZOOM but was not the trendy video-calling service Zoom Video Communications, which trades under the symbol ZM. Last year the U.S. Securities and Exchange Commission stopped trading of Zoom Technologies, partly because of confusion over its connection with Zoom Video.

Signal Advance’s sole full-time employee, Chris Hymel, did not immediately respond to a request for comment on Monday.

For many years Musk’s online utterances have attracted considerable attention. Last week Musk’s profile reached new heights as he became the wealthiest person in the world and Tesla’s market capitalization exceeded that of Facebook.

On Sunday Musk said on Twitter that he would give money to support Signal.

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