How does condition 5 of the Open Font License apply to using a font in my game/engine?

Question

For my game-engine I have created an debug-console I use for more complex operations and tests, logging, etc.

When looking for a good & clean font I considered using Google Fonts. Many if not all fonts on there are licensed under the Open Font License¹, which seems to be the real deal.

Yet when reading the license I got confused if condition 5 also applies to videogames/engines:

5) The Font Software, modified or unmodified, in part or in whole, must be distributed entirely under this license, and must not be distributed under any other license. The requirement for fonts to remain under this license does not apply to any document created using the Font Software.

^{emphasis mine}

So, how does this condition translate to me using it for my engine/game? And how would I go about properly attributing?

_{¹Link to the license definition: http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=OFL}

Answer 1

The intent of Condition #5 of the Open Font License seems to simply be to clarify the following:

1. You do need to provide this license alongside your usage of the font, but
2. This license applies just to the font, and doesn't affect whatever you're using the font to produce.

In other words, the license is clarifying that it is not a viral license such as the GPL.

It's written assuming you're creating something classical like a written document since that would be the most ordinary use case. However in a non-classical production like a game, we could reasonably interpret that the “document” just covers wherever you're using the font inside the gam. It may even be interpreted as the game itself! But since the point of the clause is to clarify that it's not affecting any of that, how much is counted as the “document” would be mostly academic.

So it should be safe to use these fonts in a game — they're not exclusively limited to plain documents.

Proper attribution is specified per condition 2 of the Open Font License:

2) Original or Modified Versions of the Font Software may be bundled, redistributed and/or sold with any software, provided that each copy contains the above copyright notice and this license. These can be included either as stand-alone text files, human-readable headers or in the appropriate machine-readable metadata fields within text or binary files as long as those fields can be easily viewed by the user.

This gives you plenty of room for how to provide attribution. There's two main options games go for:

1. If your users can access the game's files (e.g. it's not a console game), then you can distribute the license as a plain text file within your game files. If you've just got one or two OFL fonts, you might include it as foo-license.txt where “foo” is the font name. If you have many OFL fonts, just include one open-font-license.txt, and insert some lines at the top clarifying that the license text that follows applies to a specific set of fonts used within your game (and list the names of those fonts).
2. Alternately, many games include a Boring Legal Stuff section. This section is stuffed somewhere users won't find it unless they're looking for it, such as a the end of the About or Help area. It generally lists all the licenses involved in the game's production in a single endlessly scrolling text box, since that's technically sufficient to satisfy licensing requirements. You can reproduce the OFL license text in here and indicate which OFL fonts you've used that it covers.

Before releasing your game to the public for sale, it would be standard procedure to visit a lawyer to make sure you're doing things safely and legally. It would be appropriate to check with that lawyer that the above is sufficient just to cross your t's and dot your i's.

Answer 2

The Open Font FAQ Update 6 (current at the time I write this answer) has some good information on this, but nothing definitive. The license mainly describes the intention of using fonts covered by the license in documents or as a basis for creating new fonts. Information about using fonts in software is barely addressed, though there are snippets in the FAQ that can be pieced together to form a cohesive answer.

As I understand, the intention of the Open Font License is to:

• notify that the font is free to use
• ensure the font author is acknowledged for their effort whenever the font is used
• that the font license is acknowledged whenever the font is used
  • this is especially applicable when the font is used when creating new fonts; the license must be perpetuated in the new font.

As far as using Open Font License fonts in software (i.e. games in this context), I gather what I feel is the appropriate reasoning below from the FAQ below:

Question 1.4 specifically refers to using the font (original or modified) in a (sellable) game. They define this as "bundling" the font in software, and list several examples of software it applies to.

Question 1.19 talks about the "grey area" of acknowledgement. It clarifies the intent of acknowledgement as being a way to show goodwill; that you have benefitted from the font author's work (but not in a way that means the author has endorsed your game).

Question 1.20 contains the most appropriate information about bundling the font in software. The answer to 1.20 is so on-point that I'm going to quote it here in it's entirety:

If you bundle a font under the OFL with your mobile app you must comply with the terms of the license. At a minimum you must include the copyright statement, the license notice and the license text. A mention of this information in your About box or Changelog, with a link to where the font package is from, is good practice, and the extra space needed to carry these items is very small. You do not, however, need to include the full contents of the font package - only the fonts you use and the copyright and license that apply to them. For example, if you only use the regular weight in your app, you do not need to include the italic and bold versions.

Note that the question specifically targets a "small app for mobile platforms", however given the way Question 1.4 is written I believe it is applicable to all software the bundles the font. As such, if your software (game) contains a font covered by the Open Font License and is distributed on a web/mobile/desktop digital platform (i.e. pretty much anywhere you can distribute your game software, whether you are selling it or not) I believe this question applies to you.

Satisfying the OFL License in a game

Given the above information from the FAQ, I believe that games using fonts covered by the Open Font License must, somewhere in the game that a user can see, provide 3 things for each such font:

• the copyright statement
• the license notice
• the license text

This is your acknowledgement for using the font.

The FAQ recommends using the About box or Changelog, but if you don't have these things in your game you'll have to design somewhere a user can view your acknowledgement(s) of each such font you use, including these 3 things.

• For games on an operating system where the user can view text files you include in your distribution, putting the acknowledgement in one or more text files that will cover the license requirements.
• If the user can only access your running game, you'll need to put your acknowledgements somewhere in the GUI where the user can see it.

Please note that I'm not a lawyer, but in my experience working with licenses in software (which is quite a lot — I've been doing this for decades) if you can show how you've satisfied the license agreement then you're covered. The Open Font License is mainly concerned with ensuring you don't profit directly from the font author's work. If you acknowledge each font with these 3 details from the FAQ where the user can see it then you should legally be covered. When in doubt, show more information.