The U.S. Federal Trade Commission filed an antitrust lawsuit against the health information network Surescripts on Wednesday, accusing them of using illegal means to maintain monopolies over two portions of the electronic prescribing market.

Surescripts said in a statement that it was “disappointed” by the lawsuit and had been cooperating with the agency.

The FTC accused Surescripts, which provides a range of electronic records and prescribing services to doctors, pharmacists and patients, of requiring long-term exclusivity from customers and punishing them with high prices if they bought some prescriptions from another company.

Surescripts provides a network that allows health care providers to send prescriptions to pharmacies electronically. It also contacts patients’ insurance companies to determine benefit eligibility.

“Surescripts’ illegal contracts denied customers and, ultimately, patients, the benefits of competition – including lower prices, increased output, thriving innovation, higher quality, and more customer choice,” said Bruce Hoffman, the head of the FTC’s Bureau of Competition.

The FTC also accused Surescripts of illegally pressuring a corporate customer, Allscripts Healthcare Solutions Inc , to prevent them from taking their business to a competitor.

Surescripts Chief Executive Tom Skelton said in an email statement that the company has reduced the cost of electronic prescribing by 70 percent since 2009.

“We are making an important change to our e-prescribing business agreements with pharmacies by removing the loyalty provisions in those contracts. This step addresses one of the FTC’s chief concerns,” Skelton added in his statement.