SAN FRANCISCO/NEW YORK, Aug 17: Facebook Inc shares sank 6.3 per cent to a record closing low after early investors got the green light to sell for the first time since the No. 1 social network went public, starting a string of insider lockup expirations that will pressure the stock for months.

More than 270 million shares owned by early investors became available for trade on Thursday after a 3-month curb on sales ended. That’s more than half the 421 million shares sold in its initial public offering on May 18. The company founded by Mark Zuckerberg in his Harvard dorm room became the only US Company to debut with a market value of more than $100 billion.