Oct 8 (Reuters) - Three blank-check companies backed by venture investor Chamath Palihapitiya have raised a total of $2.1 billion through initial public offerings, the companies said in separate statements on Thursday.

The companies, Social Capital Hedosophia Holdings IV, V and VI, have raised up to $400 million, $700 million and $1 billion, respectively, by selling units of $10 each - made up of stocks and warrants - on the New York Stock Exchange.

Credit Suisse is the sole book-runner on the offering of Palihapitiya's companies.

A blank-check company backed by Palihapitiya merged with Virgin Galactic Holdings Inc in October last year, while his Social Capital Hedosophia Holdings Corp II is set to merge with SoftBank Group backed Opendoor Labs Inc.

A blank-check company or a special purpose acquisition company (SPAC) is a shell vehicle that uses capital raised through an initial public offering to buy a private company, usually within two years. The deal then takes the private company public.

Other high-profile investors like Bill Ackman, Michael Klein and Chamath Palihapitiya have raised billions through their SPACs this year. Ackman's SPAC Pershing Square Tontine Holdings Ltd raised $4 billion in its IPO in July, making it the largest SPAC IPO.

(Reporting by Juby Babu in Bengaluru; Editing by Arun Koyyur)