The American Dental Association and two individual dentists filed a class-action lawsuit Nov. 26 against the Delta Dental Plans Association, its affiliated national entities and 39 independent Delta Dental companies, alleging the provider network has engaged in anticompetitive conduct and violated federal antitrust laws.

The complaint alleges Delta Dental allocated territories of operation and divided the national market in order to restrict competition and reduce reimbursement rates to dentists.

"Its harm is reflected in suppression of compensation below levels that would prevail in a competitive marketplace to dentists who are members of the Delta Dental provider network, as well as in the value and choices of dental care available to patients who are subscribers to the dental insurance provided by Delta Dental," the lawsuit alleges.

The ADA filed its lawsuit in the U.S. District Court for the Northern District of Illinois.

Other individual dentists also have filed class-action lawsuits against Delta, alleging antitrust violations, according to an ADA news release. The ADA and the individual dentists are requesting the court certify the proceedings as a class action. The court will rule on that request in the coming months.