St. John Properties is a privately held commercial real estate development, ownership, and management firm that specializes in the design, development, leasing, and management of flex/research and development, office, retail, and warehouse space. Founded in 1971 by Edward St. John, the company has grown from a small local developer into one of the nation's largest privately held commercial real estate firms. The firm operates on a vertically integrated model, managing all facets of real estate development and operations in-house, including acquisitions, development, construction, leasing, interior design, and property management. The company's investment strategy emphasizes speculative development, acquiring raw land, adding infrastructure, and developing Class A properties that can be quickly customized to meet client needs. St. John Properties focuses on flex/R&D space, which serves professional services companies, office users, government contractors, retailers, light manufacturing, and warehouse/logistics users. The firm maintains a long-term hold strategy for its portfolio rather than pursuing quick sales. As of 2026, the company's portfolio includes more than 25 million square feet of commercial space and over 3,000 residential units across 13 states, with assets valued at more than $5.5 billion. The firm serves more than 2,700 clients. The company received the 2018 NAIOP National Developer of the Year award and has developed 100 LEED-certified buildings.