CommonWealth REIT is managed by Reit Management & Research LLC (RMR®). RMR is a large real estate management company which was founded in 1986 to manage public investments in real estate. As of December 31, 2013, RMR manages a large portfolio of publicly owned real estate including approximately 1,200 properties, located in 47 states, Washington, DC, Puerto Rico, Canada and Australia. RMR has approximately 850 employees in its headquarters and regional offices located throughout the country.
In addition to managing CWH, RMR also manages Hospitality Properties Trust (HPT), a publicly traded REIT that owns hotels, Senior Housing Properties Trust (SNH), a publicly traded REIT that primarily owns healthcare properties, Government Properties Income Trust (GOV), a REIT that primarily owns and leases office buildings that are majority leased to government tenants and Select Income REIT (SIR), a publicly traded REIT that is focused on owning and investing in net leased, single tenant properties. RMR also provides management services to Five Star Quality Care, Inc., a healthcare services company which is a tenant of SNH, and to Travel Centers of America, LLC, an operator of travel centers which is a tenant of HPT. An affiliate of RMR, Sonesta International Hotels Corporation, is also one of HPT's hotel managers; and another affiliate of RMR, RMR Advisors, Inc., is the investment manager of a publicly offered mutual fund, which principally invests in securities of unaffiliated real estate companies. The public companies managed by RMR and its affiliates had combined total gross assets of approximately $23 billion as of December 31, 2013. RMR is a member of the U.S. Green Building Council and an Energy Star Partner.
We believe that our relationships and arrangements with RMR provide a competitive advantage to CWH because of RMR's depth of management and experience in the real estate industry. We also believe RMR is able to provide management services to CWH at costs that are lower than we would have to pay for comparable services. CWH’s corporate expenses have historically been lower than the average corporate expenses for many other office REITs as measured both as a percentage of gross revenues and as a percentage of gross assets.