Patent licenses are necessary to enable companies to commercialize and share patented technologies. They allow other parties to use a patented invention in exchange for payment, helping patent owners monetize their inventions. Patent licenses are needed to commercialize technologies, share technology between companies, avoid costly litigation, enter new markets requiring certain patents, and access technologies needed for innovation. The document then provides guidance on determining licensing goals, conducting market research, preparing a licensing agreement, negotiating terms, and enforcing the license.