Cerebras Systems ' shares were volatile in early trading Friday after the company completed the largest IPO by a U.S. tech firm in years. The semiconductor firm initially sold shares at $185 as it started trading on the New York-based Nasdaq stock exchange, before closing at $331.07 per share. Cerebras' stock soared 68% by the closing bell, giving it a market cap of about $95 billion. The firm sold 30 million shares on Thursday, raising $5.55 billion , which is the largest IPO for a tech firm