What happened: Cerebras Systems (CBRS) stock was down nearly 5% on Friday after surging more than 68% the previous day in a highly anticipated public debut by an Nvidia (NVDA) competitor.

Cerebras stock closed at $311.07 on Thursday after reaching an intraday high of $385 each.

By the numbers: The stock opened at $350, nearly double its IPO price of $185. The price surge sent the company’s market capitalization to almost $70 billion, based on the outstanding shares disclosed in regulatory filings. On a fully diluted basis, including restricted shares, stock options, and warrants, the valuation was closer to $86 billion, according to Bloomberg data.

What else you need to know: Cerebras stock started trading under the ticker…