South Shore Health Care (“SSHC”) has been offering health care services under the “South Shore Health Care” and “South Shore Health Center” marks in Braintree since 1993. SSHC has had a Massachusetts state registration in the “South Shore Health Center” mark for “physician’s office providing primary health care (family health care), preventative medicine and occupational health services” since 1993, expanded by a subsequent 2018 registration for “medical services,” and began using the “South Shore Health Care” mark in 2008. SSHC filed an application for a federal registration on “South Shore Health Care” last month. SSHC asserts that their state and common law trademark rights are infringed by South Shore Health Systems (“SSHS”) and South Shore Health Express (“SSHE”). According to the complaint, SSHS was formed in 1922 under the name “Weymouth Hospital,” which was changed to “South Shore Hospital” in 1945. In 2016, Defendants allegedly registered the domain name <southshorehealth.org> and used it to promote not only the hospital, but also other parts of its organization, such as health care services such as South Shore Medical Center and South Shore NeuroSpine. In 2018, SSHE formally adopted that moniker, a change from its previous name “Health Provider Services Organization of the South Shore.” Defendants further moved towards partnering with or purchasing Health Express Urgent Care, a business having multiple urgent and primary care clinics in the South Shore region, triggering newspaper reporting that referred to Defendants as “South Shore Health.” Plaintiffs allege a distinct loss of business, as well as actual confusion, resulting from these actions. While Plaintiffs acknowledge that many other health care providers have used the term “South Shore” in their names (e.g. South Shore Urology, South Shore Orthopedics, and South Shore Medical Center), they assert that no other entity has used the exact three-word phrase “SOUTH SHORE HEALTH” in the 25 years that they have operated under that name. Plaintiffs further allege that Defendants have “never used their obscurely-registered corporate name” as a trademark or service mark. Plaintiffs bring claims for state, federal and common law trademark infringement, cybersquatting, and unfair competition.