NEW YORK, October 1, 1999 — OneSource Information Services, Inc. (NASDAQ: ONES), the first place professionals go for comprehensive business information on the Web, today announced that it has completed its acquisition of Corporate Technology Information Services, Inc. (CorpTech) for approximately $8 million in cash. CorpTech is a leading provider of high technology company profiles with a special focus on emerging private companies.

"Completing our acquisition of CorpTech and its comprehensive information on privately held, high technology companies better positions OneSource to address our customers’ needs and gives us greater control over editorial content," said Dan Schimmel, president and CEO of OneSource Information Services. "Acquisitions and strategic alliances are an important part of our strategy to expand the breadth and depth of our services and enhance our position as a leader in the online business information market."

CorpTech, based in Woburn, Massachusetts, is a leader in private company information, collecting research on more than 50,000 high technology businesses worldwide. With over 4,000 clients, CorpTech generated $5.2 million in revenue during its last fiscal year through multiple channels including the Web, CDs, print and third-party distributors such as OneSource.

About OneSource Information Services

OneSource Information Services, Inc. provides Web-based business and financial information to professionals who need quick access to reliable corporate, industry and market intelligence. Its Business Browser product line provides sales, marketing, finance and management professionals with textual information, such as news, trade press, executive biographies and analyst reports. Business Browser products also deliver numeric information such as company financial results, stock quotes and industry statistics. OneSource integrates business and financial information on over one million global public and private companies from more than 25 information providers drawing upon over 2,500 sources of content.

Business Browser products are designed to address information needs of leading professional and financial services firms, technology companies and other large organizations including American Express, British Telecommunications, Deloitte & Touche, KPMG, Oracle and SAP. OneSource is headquartered in Concord, MA, with offices across the United States and United Kingdom. Product information is available by calling 1-800-554-5501 in the U.S. and +44 (0)1483 241212 in the UK, and at