Is this roughly what you have in mind?
No.
(Please bear with me a bit if I say anything
really boneheaded below; I'm not a lawyer.)
To a certain extent, what I was depending on (possibly improperly so) is what Kobold Press did with Black Flag, where the Black Flag SRD, clearly to me a derivative work of the 5.1 SRD, was released in its entirety under ORC, without any marking of what material in specific was 5.1 SRD material at all. Instead, what they did was simply put the WotC-written CC-BY 4.0 notice in the attributions on the cover page of the Black Flag SRD PDF, which includes a link to the 5.1 SRD.
So, if some third party is only working directly from the Black Flag SRD, they have no idea what they could theoretically could use under CC-BY 4.0 instead of ORC. When making a derivative of the Black Flag SRD itself, a third party so working would as a practical matter have to use it all under ORC. But that's only practical; the ORC terms
don't include a prohibition on later independently going and using the 5.1 SRD under CC-BY 4.0. And it's a limited form of practical, because anyone who has the Black Flag SRD has been provided with the WotC CC-BY notice, which links them to the 5.1 SRD and CC-BY 4.0 license anyway.
All right.
Now, let's imagine I sit down and create a file that is a mixture of content directly from the SRD 5.2 (licensed under CC-BY 4.0), content directly from a work licensed under OGL 1.0a, some content derivative from the first, some content derivative from the second, and then, just as the coup de grace, some content simultaneously derivative from both parent works.
I then go and post the file with the declaration that the whole thing is Open Game Content (except for the OGL license text in the back, of course), and I include the WotC-authored, CC-BY 4.0-required, attribution statement in the "Section 15" of the OGL 1.0a.
Like with Kobold and Black Flag, I'm not telling anybody what
in specific in my file is from the SRD 5.2 so they can directly pick it out and use it under CC-BY 4.0. But they've got the WotC-authored attribution notice with a link to the SRD 5.2 and CC-BY 4.0 right there, inside the OGL Section 15, and they can go there and do that themselves.
Am I legal?
I thought so, though I'm now less and less confident in that evaluation as I poke at this.
One possibility is, if content is distributed under the OGL as Open Game Content, does that (attempt to) bind people under the OGL to only ever used the material under the OGL, even if they want to go upstream to the original licensor? Because that would violate CC-BY 4.0's 2(a)(5)(B).
Well, it looks like one possible reading of Section 2 of the OGL could be understood as such an attempt. But, nobody has ever read it that way as I understand it -- nobody was running around saying OGL's Section 2 meant people who used the SRD 5.1 under the OGL 1.0a weren't subsequently allowed to use the SRD 5.1 under CC-BY 4.0 in a later product. OGL Section 2 is a zealous guard against people trying to unilaterally redefine the OGL, not a prohibition of separate explicit licenses from an upstream copyright holder, and should be understood as such. And that CC-BY 4.0's 2(a)(5)(B) only comes into play if someone really does try to block someone downstream from going upstream.
So,the second, and more worrying possibility to me now is, am I violating the OGL 1.0a?
This I missed the first time I thought all this through.
My original thought on this was that, assuming CC-BY 4.0 is complied with, everyone has a right to "reproduce and Share the Licensed Material, in whole or in part" and to "produce, reproduce, and Share Adapted Material". And by my reading of the CC-BY 4.0 and the OGL 1.0a, those rights under CC-BY 4.0 include all the rights that the OGL 1.0a covers with "Use" (defined as "use, Distribute, copy, edit, format, modify, translate and otherwise create Derivative Material of Open Game Content").
So, through the trick of meeting the CC-BY 4.0 requirement to include the WotC attribution notice by expedient of including said notice in the Section 15 of my work, anyone complying with the OGL 1.0a would have the rights to use the CC-BY 4.0 material I labeled Open Game Content in all the same ways that anyone complying with the OGL 1.0a could "Use" Open Game Content, and thus all that material was
effectively Open Game Content.
But, the definition of Open Game Content under the license refers to stuff so designated by a Contributor, and a Contributor is defined as a copyright holder, and now we have stuff in my file, labeled by me as Open Game Content, that wasn't designated as such by a Contributor (or authorized agent thereof). That seems to be what Section 5 is trying to avoid.
On the other hand, the OGL doesn't actually say what "original material" means, either.
And it's hard to see where anyone's
interests are being affected. I don't see any violation of the CC-BY 4.0 terms, which means no violation of the rights of the copyright holder in labeling their stuff Open Game Content. And it's hard to see how anyone who has contributed their copyrighted material as "Open Game Content" under the OGL 1.0a is affected by there being stuff labeled Open Game Content that can be used in the same manner as any other Open Game Content, but wasn't specifically designated as such by a Contributor (or authorized agent thereof).
So. I'm not sure where that leaves things.
