The Techniker Krankenkasse (TK) is a replacement insurance company and therefore the provider of statutory health insurance. It is open nationwide and is one of the largest German health insurance companies with 10 million insured people. The TK is a corporation under public law with self-administration. She is a member of the Association of Replacement Funds (vdek). The health insurance company has been operating under the Die Techniker brand since September 2016.