OGL d20 modern

[ogre]

Hello again!

During the summer I queryed if making a game based off of d20 Modern was viable, meaning players of my game would need that book.
My decision was to instead use the d20 Modern SRD and change it, to suit my PA game.
So my plan is to use the OGL to reprint a lot of the d20 SRD using the combat system, vehicle combat, skills and feats, with a host of changes and additions. I'll note all of this system stuff as open game content and note closed content on some unique stuff I've made (or is it better to just open the whole thing?) Some of the core stuff has changed, like how skills are acquired, I'm not talking just new feats here.
So my big question is, am I ok in doing this? The whole 4e license and changes to the legal issues of d20 have me confused.
Any advice is appreciated.

[afstanton]

You cannot mix OGL with 4e. At all.

Ignore the "d20 System" license - it is defunct.

Only deal with the OGL for OGL stuff (and properly use Section 15), and use the GSL (or strict copyright law) for 4e stuff.

IANAL.

[Starglim]

Don't worry too much about 4e and the d20 licence if you weren't planning to use them anyway. Nothing has changed in the OGL.

The use you describe sounds fine.

As for closed content, campaign flavour is one thing, but for a commercial product, as opposed to a fan posting, I feel personally it's questionable to close or cripple game mechanics as OGC. Firstly, I don't see how it's in your interests - on the contrary, people reusing your work, if they follow the OGL correctly, increase your exposure and reputation.

Secondly, it's hard to claim that rules you wrote for d20 Modern owe nothing at all to the SRD and the designers who worked on it. Thirdly, the community contributes to your financial success and you should give something back for it.

[pawsplay]

If you do PI game mechanics, there is absolutely nothing stopping someone else from rewriting them with different names. In fact, they can use the same names but a different explanation, if you choose non-copyrightable names.

My suggestion is to OGC just about all of the rules except some setting specific items, like races or unique technologies, and then PI the long descriptions of stuff so people can't reprint your book with a different title, they will have to at least write their own fluff.