A flexible information model for systematic development and deployment of product families during all phases of the product realization process is crucial for product-oriented organizations. In this paper we propose a unified information model to capture, share, and organize product design contents, concepts, and contexts across different phases of the product realization process using a web ontology language (OWL) representation. Representing product families by preconceived common ontologies shows promise in promoting component sharing while facilitating search and exploration of design information over various phases and spanning multiple products in a family. Three distinct types of design information, namely, (1) customer needs, (2) product functions, and (3) product components captured during different phases of the product realization process, are considered in this paper to demonstrate the proposed information model. Product vector and function component mapping matrices along with the common ontologies are utilized for designer-initiated information exploration and aggregation. As a demonstration, six products from a family of power tools are represented in OWL DL (Description Logic) format, capturing distinct information needed during the various phases of product realization.