Corporate Membership is by election through the existing Member Companies and is open to firms actively engaged in industrial research and innovation, with a substantial patent portfolio. Members are usually significant players in their own industrial sector and have a major presence or at least an affiliated company in Europe. The PDG corporate membership includes many well-known blue chip companies with a strong R&D focus, representing all major areas of technology. Member Companies, through their Main Delegates or other interested staff, are expected to participate actively in at least one of the PDG Working Groups and / or other activities, for example by contributing to discussions, participating in tool testing and evaluations, sharing/presenting (non-confidential or anonymised) best practices/issues/etc. from their company, or hosting meetings. Notwithstanding normal commercial confidentiality and anti-trust guidelines, all Member Companies are encouraged and expected to cooperate with other Member Companies within the framework of PDG activities.