Annapolis (Map, News) - Annapolis-based USinternetworking, often referred to as USi, will be absorbed into AT&T Inc. under a $300 million cash and assumed debt deal that will leave the current management and employees in place, the companies announced Tuesday.

The deal is expected to close in the fourth quarter, according to a joint release by the companies. USi is a privately held company.

USi sells computer “application management,” which includes software management tools and solutions for companies to manage their Internet-networking needs.

It also includes remote management of a company’s network and development and hosting of their internal Internet applications.

USi, which operates in more than 30 countries, has more than 150 customers, including Sunoco Inc., Wachovia Corp. and the American Cancer Society.

“The USi team is excited to be joining forces with AT&T,” said Andrew A. Stern, USi’s chairman and chief executive officer.

“Over the past eight years, USi has developed an unmatched ability to deliver enterprise-scale applications as fully integrated, on-demand services. Combining our capabilities with AT&T’s global footprint creates an unparalleled opportunity for growth and the basis for continued market leadership for years to come.”

Stern will act as chief executive officer of the AT&T subsidiary when the deal is closed in the fourth quarter.

USi will operate as a wholly owned subsidiary and business unit within AT&T’s existing enterprise services organization, which is led by group President Forrest Miller.

“The addition of USi’s technology and expertise in applications management to AT&T’s global reach, networking expertise and extensive hosting capabilities will broaden the range of solutions for our customers,” Miller said.

eeldridge@baltimoreexaminer.com