Castle Information Systems Inc., a web and mobile app company, raised $529,000 in a private equity offering, according to a filing Friday with the Securities and Exchange Commission.

The company raised the money from two investors and is seeking to raise an additional $271,000, according to the filing.

The company raised $875,000 back in August 2016.

Raleigh-based Castle Information is best known for its Blerbal app.

A week after its 2011 offering, the company applied to trademark the Blerbal mobile app, according to the U.S. Patent and Trademark Office. The app allows users to report news and information to their communities and groups.

David Cozart is the president of Castle Information Systems, which was previously called Swamp Castle.

Companies relying on a Reg D exemption do not have to register their offering of securities with the SEC, but they must file what’s known as a Form D electronically with the SEC after they first sell their securities.