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In licenses such as that of libjpeg and freetype, there are clauses like the following:

(2) If only executable code is distributed, then the accompanying documentation must state that "this software is based in part on the work of the Independent JPEG Group".


o Redistribution in binary form must provide a disclaimer that states that the software is based in part of the work of the FreeType Team, in the distribution documentation.

Is putting a notice in a text file in the installation directory enough? Or is a more obvious notice typically needed? For a non-open-source end application, what's the usual way to display these mandatory acknowledgments?

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if their license is copyleft, as opposed to merely open-source, then any application that uses them would need to also be open source. suggest you edit the title. – TZHX Apr 2 '11 at 7:51
@TZHX, ah, indeed. Although the LGPL is copyleft and allows closed-source apps to use LGPL libraries, under certain conditions. – bdonlan Apr 3 '11 at 5:04
up vote 6 down vote accepted

Most of the applications that I've seen include a note in their Help > About box, EULA, or web site that says, basically, "For information on third party licenses, see url or document." For example:

  • includes the following clause in its EULA: "Third Party Code. Additional copyright notices and license terms applicable to portions of the Software are set forth in the THIRDPARTYLICENSEREADME.html file." Within the third party license readme file, each library gets its own section with wording similar to the following:
    The following software may be included in this product:William's Wonderful Widgets; Use of any of this software is governed by the terms of the license below:
    Copies of the LGPL and GPL are included at the end.
  • Google Chrome includes a notice in its Help > About screen: "Google Chrome is made possible by the Chromium open source project and other open source software." "Open source software" here is a link bringing up a credits page that lists each component, its homepage, and its license.
  • VMware devotes a section of their web site to collecting all of their open source licenses and source code and includes a link to this site in their EULA. Installation directories also include license lists similar to's.
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Sounds like a good question for the folks over at the Free Software Foundation.

If I were you, I would pop into the #fsf IRC channel over on Freenode and ask the question there.

If you don't have an IRC client handy and aren't interested in installing one:

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If you do find an answer in IRC, please be kind to others and post the answer here in a comment or alternate answer. Other people have an interest in the answer to this question :) – Jeff Welling Apr 2 '11 at 7:22

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