Politics 17 August 2012 Facebook shares plunge to all time low End of lock-up period prompts selling spree. Sign up for our weekly email * Print HTML Facebook shares fell to a new low last night as the first lock-up period ended, meaning some of the company's early investors could cash their holdings. Investors who had sold some of their stock in May had been stopped from further selling for 90 days, but as this time ended the sudden large volume of selling suggested a rush for the door. 271 million shares became available for sale on the stock market last night, and the stock fell to almost half the IPO. The latest glitch in the Facebook flotation saga continues its career as most disastrous flotation in tech industry history. › Edinburgh diary: Who are these reviewers, then? Facebook. Photograph: Getty Images Subscribe from just £1 per issue More Related articles Jeremy Corbyn has found a vulnerable spot on Theresa May and trade Politicians are worried that their pensions are destroying the planet. Is yours? Nap Store: Where did all these new mattress start-ups come from?