DCO

Developer Certificate Of Origin
In November 2015, the HAT development community decided to standardize on a requirement to adhere to a Developer Certificate of Origin (DCO) for contributions to the HAT open source stacks.
The full text of the DCO version 1.0 (the current version as of 2016) is:
       Developer's Certificate of Origin 1.0

        By making a contribution to this project, I certify that:

        (a) The contribution was created in whole or in part by me and I
            have the right to submit it under the open source license
            indicated in the file; or

        (b) The contribution is based upon previous work that, to the best
            of my knowledge, is covered under an appropriate open source
            license and I have the right under that license to submit that
            work with modifications, whether created in whole or in part
            by me, under the same open source license (unless I am
            permitted to submit under a different license), as indicated
            in the file; or

        (c) The contribution was provided directly to me by some other
            person who certified (a), (b) or (c) and I have not modified
            it.

        (d) I understand and agree that this project and the contribution
            are public and that a record of the contribution (including all
            personal information I submit with it, including my sign-off) is
            maintained indefinitely and may be redistributed consistent with
            this project or the open source license(s) involved.



Example
Here is an example Signed-off-by line, that indicates the submitter accepts the DCO:
Signed-off-by: John Doe <john.doe@hisdomain.com>