FORTUNE — Private equity firm Welsh Carson Anderson & Stowe is in talks to acquire Alert Logic., a Houston-based provider of SaaS solutions for the cloud, according to an FTC filing.

Sellers would be the venture capital firms that have invested nearly $50 million into Alert Logic since 2005, including Access Venture Partners, Covera Ventures, Mercury Fund, OCA Ventures and Updata Partners.

Alert Logic is private, but recently disclosed that it is “tracking ahead” of its plan to reach a $50 million revenue run-rate by the end of 2013. This includes $10.1 million in Q2 revenue, which is a 43% year-over-year increase and a 7% bump from Q1 2013.

More than 2,200 customers are using the company’s SaaS solutions, which are designed to secure the application and infrastructure stack.

Fortune has left a message with Alert Logic, and will update this post if it responds.

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