IBDI - Overview of Open Source Licenses

This brief overview is provided in order to help IBDI participants and other interested parties to understand the concepts of the open source movement. You are invited to your own contributions and comments on the issue.

In general, all open source distributions provide users with complete source code. However, different groups have different views on users' rights to modify the source code and distribute their products, hence a variety of licences exists.

Licenses Designated as `classic' by Open Source Initiative (OSI)

Full list of licenses certified by OSI

Mozilla Public License, MPL

Related Links

Contributed Comments

on BSD License:

Briefly, the BSD licence does allow re-licensing as a commercial product. Hence SunOS and other Unix flavours are derived from Berkeley Unix which is also what *BSD is based on. There are many examples of BSD licenced software being used commercially, e.g. the DBM libraries.

The licence states:

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. Neither name of the nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

Notice you can distibute binary only executables, in modified form - i.e. you can take the code from a BSD product, and compile it into your program and do whatever you want with your program. You used to have to advertise (e.g. in the About box) that you had used the code, but you no longer have to.
This is well known and is one of the problems or benefits of the BSD licence, depending on your point of view.

on Mozilla (MPL-1.1):

The license distinguishes Initial Developer(s) from Contributor(s), all modifications made to the code must be documented so either of the parties is responsible for their particular part of work.

Source code must be available, either along with binaries or via electronic media. Developers and contirbutors are responsible for source availability even if it's hosted by the third party.
Particular parts of the License (eg Exhibit A) must be duplicated inside the source code.

From 3.6 Distribution of Executable Versions
You may distribute the Executable version of Covered Code or ownership rights under a license of Your choice, which may contain terms different from this License, provided that You are in compliance with the terms of this License and that the license for the Executable version does not attempt to limit or alter the recipient's rights in the Source Code version from the rights set forth in this License. If You distribute the Executable version under a different license You must make it absolutely clear that any terms which differ from this License are offered by You alone, not by the Initial Developer or any Contributor.

I understand it so that it's possible to fork, commercialise and close the product if only one takes the whole responsibility for it.

From 4. Inability to Comply Due to Statute or Regulation
If it is impossible for You to comply with any of the terms of this License with respect to some or all of the Covered Code due to statute, judicial order, or regulation then You must: (a) comply with the terms of this License to the maximum extent possible; and (b) describe the limitations and the code they affect. Such description must be included in the LEGAL file described in Section 3.4 and must be included with all distributions of the Source Code.

How much would it cost to find a lawyer that digs out a paragraph in the US Export Regulations? Also, see Amendments IV, which makes it possible for Netscape not to open specific portions of code due to their prior contractual obligations.

The whole thing is full of thereofs and hereunders. If you run it through a compressor, you'd probably get something like this: the code remains open to the extent and as long as interested parties find it reasonable.

More on MPL from :

Currently online depositories rarely provide users with possibility to search programs by license types. However, here's a brief collection of random links that point to software available under MPL.


Also, nearly all projects listed at Delphree are available under MPL.

Another interesting resource can be found here. This is an exit strategy for ROADS project. Their funding is running out and they seem to have found the way to keep it up and running.

On the above MPL comment:
>From 4. Inability to Comply Due to Statute or Regulation
MPL has a solution to problems with patents (or export restrictions issues) pending on parts of opensourced code. Other licenses doesn't provide this solution. Whether is good or bad depends on point of view.
>The whole thing is full of thereofs and hereunders. If you run it
>through a compressor, you'd probably get something like this: the code
>remains open to the extent and as long as interested parties find it
It's not true. Once opened code can't be withdrawn under any OSS license. Of course, MPL allow to use OSS in closed product, but MPLed parts must be still open (in some way, i.e. you provide a link to original distributor or provide it yourself along your site/distribution).

Comments on licenses are copyright to their respective authors.
This review is NOT legal advice.


  • (Coordinator; comments on Mozilla license)
  • (comments on BSD license and links)
  • (comments on Mozilla license and links)
  • (Posted 'Cathedral and Bazaar' link)