Freddie Mac operates in the secondary mortgage market in the United States. The company purchases residential mortgage loans originated by lenders, as well as invests in mortgage loans and mortgage-related securities. It operates in three segments: Single-family Guarantee, Multifamily, and Capital Markets. The Single-family Guarantee segment purchases, securitizes, and guarantees single-family loans; and manages single-family mortgage credit risk. This segment serves lenders, including mortgage banking companies, commercial banks, community banks, regional banks, credit unions, housing finance agencies, savings institutions, and other non-depository financial institutions. The Multifamily segment engages in the purchase, sale, securitization, and guarantee activities in multifamily loans and securities through the issuance of multifamily K and SB certificates; issuing and guarantying other securitization products; issuing other credit risk transfer products; and provision of other mortgage-related guarantees, as well as post-construction financing to apartment project operators. The Capital Markets segment invests principally in mortgage-related securities and single-family performing loans. This segment serves banks and other depository institutions, insurance companies, money managers, central banks, pension funds, state and local governments, real estate investment trusts, brokers and dealers, and lenders. Freddie Mac was founded in 1970 and is headquartered in McLean, Virginia.