Remix Compatibility Charts

When making a remix of two works A and B — a new work with sufficient creativity to warrant its own independent copyright, but which is also simultaneously a derivative of both A and B — it may be that the copyright statuses of A and B make it impossible to create that remix legally, or at least they may impose some conditions on the copyright status which may be put on the new work, or on how the new work is used.

Notes:

1. The scenario we are imagining is where the remixer is a different person (or entity) from the rightsholders of the original works A and B.
   1. If, instead, the remixer owns the rights to both A and B, then they may do anything they want.
   2. If the remixer owns the rights to one of A or B but not the other, then this is essentially a situation where the remixer is making an adaptation of one other person's work ... in which case, please consult the Adaptation Status Chart for much more information.
   3. That "owns the rights" we've just used twice is carrying a lot of baggage: as is shown in the Adaptation Status Chart, sometimes a work that seems to be free of others' ownership — even in the public domain! — can have some restrictions on it, such as requirements of attribution or only non-commercial use. Caution is therefore advised in remixing original works A and B of complicated provenance.
2. Additionally, we are imagining that the remixer wants to do their work without direct, specific permission of the other rightsholder(s) for the works A and B — if something is not permitted below and is important to the remixer, they always have the option of contacting the original rightsholder(s) and requesting that particular permission.

With that background understood, here is the full chart:
 

 
(We should mention that this chart is easy to make, if only one has access to the Adaptation Status Chart: this chart is answering the question if there is any single legal status which can be put on both a remix of A and of B at the same time -- i.e., if there is one column in the Adaptation Status Chart which has some entry other than the  NO  for both the rows corresponding to A's status and B's status.)

 
All abbreviations and symbols are links to the right spot in the Key, below.
 

Key to Abbreviations 1

Abbreviation	Meaning
PD	"Public Domain." This may be indicated on the work by a mention of the CC0 Public Domain Dedication tool and/or with its symbol , or by the Public Domain Mark , or the adapter may simply know, e.g., because of its age, that a work is in the public domain.
BY	Creative Commons Attribution license, often indicated by the symbol .
BY-SA	Creative Commons Attribution-ShareAlike license, often indicated by the symbol .
BY-NC	Creative Commons Attribution-NonCommercial license, often indicated by one of these symbols, depending upon region or .
BY-NC-SA	Creative Commons Attribution-NonCommercial-ShareAlike license, often indicated by one of these symbols, depending upon region or .
BY-ND	Creative Commons Attribution-NoDerivatives license, often indicated by the symbol .
BY-NC-ND	Creative Commons Attribution-NonCommercial-NoDerivatives license, often indicated by one of the symbols or .
ARR ©	“All-rights-reserved copyright.” This is the traditional form of copyright outside of open licensing approaches. It may be indicated on a work with the copyright symbol © together with the phrase “all rights reserved,” but not always: some works have the symbol © and then go on to add a Creative Commons license statement (since CC licenses are built on top of copyright!), and some works have no copyright statement at all but fall into the domain of all-rights-reserved copyright as a default.
GREAT	This remix is permitted without any additional permissions or conditions.
GOOD	This remix is permitted without any additional permissions under the condition: the remix, as well as any downstream adaptations which may be made in the future which have enough shared expression with whichever of works A and/or B was under a CC license to be considered as adaptations of those works, must give attribution to the original CC-licensed work(s) and creator(s).
CARE	This remix is permitted without any additional permissions under the condition: the remix, as well as any downstream adaptations which may be made in the future which have enough shared expression with whichever of the original works was under NC to be considered as adaptations of that work, may only be used for NonCommercial purposes and must give attribution to both original works and creators.
NO	This remix is not permitted without additional permissions.

 
This then leaves the question: which licenses may be used on the remix when the chart shows it is permissible? First of all, clearly we can concentrate on the upper-left 5×5 portion of this chart, since all the rest of it shows the remixes to be impermissible. For that corner, we have the following more detailed chart showing which of the various possible statuses into which a user might think of putting a remix is permissible, and which might be the additional constraints which might then apply:

 
This chart has exactly the same copyright status acronyms as the one above (so we do not repeat their definitions, and their links go to the key above), and very similar result codes/colors, with only one new result possible: