Twitter now employs more than 2,300 people, according to a new filing, and nearly half of them were hired in the last year.
The company’s rapid hiring ahead of its IPO, which is planned for next month, is reflective of how quickly it has built up an advertising business out of practically nothing. Fewer than 100 people worked for Twitter at the start of 2010.
Twitter recently moved into new headquarters in San Francisco, where its rent is scheduled to escalate above $500,000 a month over the next six years. It also pays $100,000 a month merely for access to a large deck on the 9th floor.
But Twitter has already outgrown that space and is looking to lease another 320,000 square feet next door.
Filings with the US Securities and Exchange Commission show that Twitter employed about 1,200 people on September 30, 2012. That figure grew to 1,700 at the end of the first quarter this year, 2,000 at the end of the second quarter, and 2,300 at the end of the third quarter.
The photo above, of Twitter’s headquarters, is by Scott Beale/Laughing Squid and used under a Creative Commons license.