Using the Open Game License

1. Include the entire text of the Open Game License (OGL) in your product.

2. Clearly indicate what content in your product is Open Game Content (OGC) and what is Product Identity (PI).

3. Update s15 of the OGL in your product with copyright notices for your product and any products from which you have used OGC.

Include the entire text of the Open Game License (OGL) in your product

This part is easy. Most products simply have a page at the back of the book containing the text of the OGL. If your product is a website, create a web page with the text and link to it from any pages which contain Open Game Content (OGC).

Clearly indicate what content in your product is Open Game Content (OGC) and what is Product Identity (PI).

OK, some definitions.

System Reference Document (SRD), a document which publishers use to house their Open Game Content (OGC). It’s not required, but it’s the method WotC uses to clearly identify their OGC, and it’s the method we use (thus this website). Paizo also used it, though they called theirs the ‘Pathfinder Reference Document’ (PRD).

Open Game Content (OGC) is material which has been designated so by its creator or publisher. For example, the whole or most of a System Reference Document (SRD) is usually OGC. You are free to designate what parts of your product are OGC in any way you wish, but it should be clear. Something designated as OGC can be re-used, distributed, and modified by other users of the OGL—that’s how you’re able to use the contents of WotC’s System Reference Documents, which are nearly all OGC (save some specific terms called out as Product Identity).

"Open Game Content" means the game mechanic and includes the methods, procedures, processes and routines to the extent such content does not embody the Product Identity and is an enhancement over the prior art and any additional content clearly identified as Open Game Content by the Contributor, and means any work covered by this License, including translations and derivative works under copyright law, but specifically excludes Product Identity.

Note that any material derived from OGC has to be OGC. You can’t take magic missile from the SRD, change a couple of things, and then declare the result PI.

Product Identity (PI), not to be confused with Intellectual Property (IP), is a term defined in the OGL. It is content which cannot be used or referenced under the OGL. WotC declares some monster names, character names, brand names, etc. as PI.

"Product Identity" means product and product line names, logos and identifying marks including trade dress; artifacts; creatures characters; stories, storylines, plots, thematic elements, dialogue, incidents, language, artwork, symbols, designs, depictions, likenesses, formats, poses, concepts, themes and graphic, photographic and other visual or audio representations; names and descriptions of characters, spells, enchantments, personalities, teams, personas, likenesses and special abilities; places, locations, environments, creatures, equipment, magical or supernatural abilities or effects, logos, symbols, or graphic designs; and any other trademark or registered trademark clearly identified as Product identity by the owner of the Product Identity, and which specifically excludes the Open Game Content;

It’s important to remember that Product Identity is not a copyright or ownership claim (although copyrighted terms and trademarks can be included)—it is a list of things you agree not to reference in exchange for access to the Open Game Content. Essentially, you’re agreeing to a contract—you won’t use those terms, and in exchange, you can do what you want with the OGC. Note that ‘trade dress’ is also listed.

So, you need to clearly indicate in your product what is OGC and what is PI. There are ways to do this — a clear statement, maybe color-coding, maybe divide your product into sections; it’s up to you. Generally you’d want to keep your product title, character names, place names, etc. as PI and your mechanics as OGC.

WotC’s Product Identity. Here’s how WotC does it. This is the content which Wizards of the Coast designates as PI in its SRD—some brand names, place names, and a handful of iconic monsters, mainly.

The following items are designated Product Identity, as defined in Section 1(e) of the Open Game License Version 1.0a, and are subject to the conditions set forth in Section 7 of the OGL, and are not Open Content: Dungeons & Dragons, D&D, Player’s Handbook, Dungeon Master, Monster Manual, d20 System, Wizards of the Coast, d20 (when used as a trademark), Forgotten Realms, Faerûn, proper names (including those used in the names of spells or items), places, Underdark, Red Wizard of Thay, the City of Union, Heroic Domains of Ysgard, Ever-­Changing Chaos of Limbo, Windswept Depths of Pandemonium, Infinite Layers of the Abyss, Tarterian Depths of Carceri, Gray Waste of Hades, Bleak Eternity of Gehenna, Nine Hells of Baator, Infernal Battlefield of Acheron, Clockwork Nirvana of Mechanus, Peaceable Kingdoms of Arcadia, Seven Mounting Heavens of Celestia, Twin Paradises of Bytopia, Blessed Fields of Elysium, Wilderness of the Beastlands, Olympian Glades of Arborea, Concordant Domain of the Outlands, Sigil, Lady of Pain, Book of Exalted Deeds, Book of Vile Darkness, beholder, gauth, carrion crawler, tanar’ri, baatezu, displacer beast, githyanki, githzerai, mind flayer, illithid, umber hulk, yuan‑ti.

Update s15 of the OGL in your product with copyright notices for your product and any products from which you have used OGC.

This is the hardest part. Let’s look at Section 15 of the OGL. The ‘stock’ OGL in the 5E SRD looks like this:

15 COPYRIGHT NOTICE
Open Game License v 1.0 Copyright 2000, Wizards of the Coast, Inc.
System Reference Document 5.0 Copyright 2016, Wizards of the Coast, Inc.; Authors Mike Mearls, Jeremy Crawford, Chris Perkins, Rodney Thompson, Peter Lee, James Wyatt, Robert J. Schwalb, Bruce R. Cordell, Chris Sims, and Steve Townshend, based on original material by E. Gary Gygax and Dave Arneson.

To that you would add your own copyright entry, such as:

Jane’s Book of Feats, Copyright 2023 Jane’s Publishing Co.

You can phrase and format it how you wish as long as it’s a copyright notice. Include authors, URLs, etc. if you want. In our Level Up books, we add these entries:

Level Up: Advanced 5th Edition Adventurer's Guide. Copyright 2021, EN Publishing. www.levelup5e.com
Level Up: Advanced 5th Edition Trials & Treasures. Copyright 2021, EN Publishing. www.levelup5e.com
Level Up: Advanced 5th Edition Monstrous Menagerie. Copyright 2021, EN Publishing. www.levelup5e.com

That all assumes you are simply making a 5E product, and referring only to the 5E SRD (which is the minimum you can include in s15). But what if you are referencing content from another product which has been released under the OGL? In that case you have to copy any copyright notices in the s15 of that product into your own s15. In that way the chain of OGC accreditation is preserved. If you look at our Level Up books, you’ll see we reference a wide array of OGC works, including the SRD for 3.5, Necromancer Games’ Tome of Horrors, and more.

For example, you might be making a Pathfinder product, not a 5E product. You are basing your work off the Pathfinder Roleplaying Game Reference Document (PRD), which is Paizo’s equivalent of an SRD. You look at the s15 of that document, copy the entire s15 (yes, no matter how long it is—some of these viral attributions can get very long) and put it in your s15. Don’t forget to add your own copyright notice in addition.

This applies to any OGC you use. If it’s from a book, look at the OGL in that book, copy the s15, and add your own copyright notice. If it is from an SRD, do the same.

If there are duplicate copyright notices, you only have to include each once.

Dos and Don’ts

• DON’T refer to any trademarks in your OGC product without written permission. s7 of the OGL is clear on this!

• DON’T refer to anything which has been designated as Product Identity (PI).

• DO make it clear which parts of your work are Open Gaming Content (and remember, if it’s derived from OGC, it has to be OGC).

• DO include the OGL in your work and update s15 to include all the copyright notices you need.

I Don’t Agree With This—What About Copyright?

The OGL doesn’t deal with copyright. Think of it as a contract—you are agreeing to certain things, incuding the Product Identity Designations and other restrictions, in exchange for free access to the whole body of Open Game Content. You don’t have to agree to that—in that case don’t use the license, and make your product using some other mechanism. But remember, this is not legal advice—be sure to get expert opinions!