Kaneohe Ranch Management Limited manages the real estate owned by the family of Harold K.L. Castle and Alice H. Castle, and their non-profit charitable foundation, the Harold K.L. Castle Foundation. The real estate portfolio consists of land holdings located in Kailua on the windward side of Oahu, Hawaii, as well as other Oahu and mainland United States properties. The Kailua properties include commercial, retail, office, industrial and residential parcels.

The Harold K.L. Castle Foundation was founded in 1962 by Harold K.L. Castle.