From Canon:
Firmware Version 1.3.4 incorporates the following improvements.
Cinema lenses which benefit from the new firmware udpate:
Support
Canon USA will perform Factory Updates on the EOS-1D C free of charge. Shipping and handling charges may apply. Please contact the Canon Customer Support Center for details.
This information is for residents of the United States and Puerto Rico only. If you do not reside in the USA or Puerto Rico, please contact the Canon Customer Support Center in your region.
If you have not already done so, please register your Canon EOS-1D C Cinema EOS Camera. By registering, we will be able to notify you via email about future announcements.
Contact Information for Inquiries
Canon Customer Support Center
Phone: 1-855-CINE-EOS (toll free), 1-855-246-3367
TDD: 1-866-251-3752
Email: CinemaEOS@cits.canon.com
Adorama carries the Canon EOS-1D C Cinema Camera.