"OCP mandates open formats and interfaces, interoperability and
freedom of movement for users between systems. It expects vendors
to cooperate with freely available, patent free or royalty free,
standards and collaborate in open processes. Although open source
does play a key role in the OCP, it only requires 'multiple full,
faithful and interoperable implementations' of standards with at
least one implementation being open source, so as to provide users
with one open alternative."