MRSO, Inc. operates a platform that manages reservations for medical check-ups. It offers Health Care Plat Form (HCPF), DX, and Large-scale vaccination services. HCPF service offers medical checkup and medical checkup online reservation service by MRSO.jp. DX service handles web reservation service using the homepage-based medical checkup and medical examination web reservation system (MRS). Large-scale vaccination service provides web reservation for vaccination of new type of coronavirus. The company was founded by Tsunegoro Nishino on February 6, 2015 and is headquartered in Tokyo, Japan.