The comedian's lawyer, Monique Pressley, said in a statement obtained by ABC News that Tamara Green, Therese Serignese, Linda Traitz, Louisa Moritz, Barbara Bowman, Joan Tarshis and Angela Leslie have made "malicious, opportunistic and false and defamatory" comments about him.
The lawsuit was filed today in United States District Court for the District of Massachusetts, Western Division, Pressley said.
Green, who in 2006 told People magazine that Cosby drugged and groped her, filed a defamation suit against Cosby last December. This year, Serignese, Traitz, Moritz, Bowman, Tarshis and Leslie joined the suit.
"Mr. Cosby states plainly that he neither drugged nor sexually assaulted the defendants and that each defendant has maliciously and knowingly published multiple false statements and accusations from Fall 2014 through the current day in an effort to cause damage to Mr. Cosby's reputation and extract financial gains," Pressley stated. "Mr. Cosby's suit further states that defendants' multi-decade old, false, uncorroborated, opportunistic allegations of sexual assault have caused and continue to cause him to suffer substantial injuries and damages to reputation, business contracts, shame, mortifications, damages to property, business, trade, profession and occupation."
Cosby, 78, has been accused by dozens of women of sexual assault, drugging, or rape. Through his attorneys, he has repeatedly denied allegations of wrongdoing and has never been charged with a crime.
"Mr. Cosby now requests that the federal court provide him relief from the defendants' intentional campaign to assassinate his character for their own financial gain by awarding him compensatory and punitive damages to the maximum extent permitted by law, by permanently enjoining defendants from continuing their intentional, extreme, outrageous and morally repugnant conduct, and by requiring them to publicly retract and correct their defamatory statements," his lawyer added.
Joseph Cammarata, an attorney who represents all seven women, said "no one should be surprised" at Cosby's lawsuit.
"It's a standard defense attorney’s play," he said.
"My seven clients intend to vigorously proceed with their case and move forward as expeditiously as possible to get their day in court because each one of them are confident that their good name and reputation will be restored at the end of the day," Cammarata told ABC News. "They will be found to be the truth-tellers."