A group of Massachusetts’s hospitals has gone to Superior Court, asking that it stop the acquisition of South Shore Hospital and Hallmark Health by Partners Healthcare.

Beth Israel Deaconess Medical Center, Lahey Health Systems, Tufts Medical Center, and Atrius Health argue Partners’ expansion reduces competition and drives up costs for the consumer.

They request the court to intervene and give the public an opportunity to comment on that expansion, which was recently given final approval by the Attorney General’s office.

Partners responded by saying they are focused on delivering more coordinated care to patients closer to their homes and in lower cost settings.