H.264 (ISO/IEC 14496-10)

http://www.iso.org/iso/catalogue_detail.htm?csnumber=56538

Price 294 CHF

http://webstore.iec.ch/Webstore/webstore.nsf/ArtNum_PK/44740?OpenDocument&mlref=JP

Price 323.- Swiss Franc

PDF version second edition dated 2004-10-01 http://jongyeob.com/moniwiki/pds/upload/14496-10.pdf

http://webmink.com/essays/h-264/

Free from vendor capture?

Maintained by open not-for-profit organisation?

Specification freely available?

Specification is copyrighted and sold by ISO and others. These are the terms of use according to the 2004 version I found:

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO's member body in the country of the requester.

Royalty-free?

The patent license organization MPEG-LA holds and enforce key patents required to implement H.264, and require royalties for most use of H.264. Creation and distribution require royalties, while some kind of playback are royalty-free until at least 2016.

No constraints on re-use?

Conclusion