Simon Phipps expresses some concerns about WebM in ComputerWorld UK. "Firstly, the new license Google is using for the project is one that's not been submitted to the Open Source Initiative for approval. As it stands it possibly can't be approved due to Google's ironic inclusion of a 'field of use' restriction in the patent grant (which is restricted to 'this implementation of VP8' rather than the more general grant in the Apache license from which the text started). That means WebM is not currently open source, despite using a license based on the BSD and Apache licenses."
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