NEW YORK (TheStreet) --Facebook (FB - Get Report) shares plunged on more than four times its average daily volume as a lock-up period expired on Thursday.

Courtesy of research firm Sterne Agee, here's a look at the rest of the lock-up schedule.

More than 270 million shares were eligible to trade, as insiders and early investors were given the chance to sell a portion of their holdings. As part of Facebook's IPO in May, there was an agreement for an additional 2 billion shares to come on the market over the next nine months. Thursday's lockup expiration is just the first of several over the next nine months.

Facebook shares plunged in Thursday trade, off 6.23% to $19.88, on 156.7 million shares, more than five times its average daily volume.

Interested in more on Facebook? See TheStreet Ratings' report card for this stock.

Follow TheStreet Tech on your wireless devices.

-- Written by Chris Ciaccia in New York

>Contact by Email.