Senior Housing Properties Trust is a real estate investment trust organized under the laws of the state of Maryland on December 16, 1998. It owns and operates independent living and assisted living communities, continuing care retirement communities, nursing homes, wellness centers and medical office, clinic and biotech laboratory buildings located throughout the United States. The Company operates in four segments. The first operating segment includes triple net senior living communities that provide short term and long term residential care and dining services for residents. Properties in this segment include leased independent living communities, assisted living communities and skilled nursing facilities. The second operating segment includes managed senior living communities that provide short term and long term residential care and dining services for residents. Properties in this segment include managed independent living communities and assisted living communities. The third operating segment includes properties where medical related activities occur but where residential overnight stays and dining services are not provided. Properties in this segment include MOBs. The fourth operating segment includes the operating results of certain properties that offer fitness, wellness and spa services to members. The Company owns approximately 375 properties (401 buildings) located in 40 states and Washington, D.C (including 14 properties (17 buildings) classified as held for sale).