Builders FirstSource, a supplier of building materials and services, agreed to acquire Cornerstone Building Alliance, the largest independently operated supplier of building materials in Arizona, for $400m. "This transaction provides incredible opportunities for our customers and employees. We have grown this business into an industry leader and joining the Builders FirstSource family is a clear win for all stakeholders, representing the next chapter in Alliance’s successful journey. We are thrilled to continue to provide exceptional products and services to our customers as part of Builders FirstSource. The future of Alliance is very bright," True Carr, Alliance Managing Partner.