Marquis Companies | 7,811 followers on LinkedIn. Marquis Companies is a fifth-generation, family-owned senior living healthcare company headquartered in Portland, OR. At our facilities in Oregon, California and Nevada, we provide exceptional, person-centered care across services and living options, including post-acute rehab, assisted living, independent living, memory care, home health care and more. Over more than 30 years, Marquis has established itself as a national leader in the profession, and a place where employees can be themselves, advance their careers and help seniors live the best, rest of their lives.