Secretive software company Palantir Technologies raised nearly $880 million in a new funding round, according to a regulatory filing available on Thursday.

The investment round came with a valuation of approximately $20 billion, according to US media reports.

The California company specializes in data analysis and counts among early investors an In-Q-Tel venture capital firm that focuses on "innovative technology solutions to support the missions of the Central Intelligence Agency and broader US Intelligence Community."

The privately held firm's services are used for financial fraud investigations as well as in counterterrorism efforts.

A form filed with the Securities and Exchange Commission indicated the funding round was launched in July but did not disclose the identities of the eight investors taking part.

The amount of money raised was reported to be $879,829 million.

Palantir, based in the Silicon Valley city of Palo Alto, did not respond to an AFP request for comment.

The reported valuation puts Palantir behind only ride-sharing firm Uber and lodging service Airbnb in the herd of 'unicorn" privately-funded startups valued at more than a billion dollars based on investment rounds.