WebMD ( HLTH) said Monday it will buy St. Louis-based Advanced Business Fulfillment for $110 million in cash, and could possibly pay an additional $150 million if certain requirements are met.

Privately held Advanced Business Fulfillment is a provider of health care paid-claims communication services for third-party administrators and health insurers. For the year ended Dec. 31, 2002, the company had pretax income of $8 million and revenue of $63 million.

WebMD said it will pay up to an additional $150 million to Advanced Business starting in April 2004 and spanning over three years if certain milestones are met that would bring substantial incremental earnings. The payments will be made in WebMD common stock or in cash, at WebMD's discretion.

"ABF brings to WebMD an excellent and innovative management team with a focus on developing products that reduce operational costs for third-party administrators and health plans," said WebMD CEO Roger Holstein. "This further enhances WebMD's ability to work with its customers to improve the effectiveness of health plan administration by managing customers' paper, EDI and Internet-based transactions."

WebMD expects to complete the acquisition in the early part of the third quarter. Shares of WebMD, Elmwood Park, N.J., closed at $11.02 Friday on the Nasdaq.