The db4o software is protected by copyright and other intellectual property laws and you must have a valid license to the db4o software or you will be breaking these laws (e.g., committing a copyright infringement). db4objects, Inc. currently offers the db4o software under both a commercial license and under the GNU General Public License (GPL). This document clarifies db4o’s interpretation of the GPL, in the event that you elect to license the db4o software under the GPL.

The GPL license to the db4o software costs essentially nothing, but comes with significant restrictions that typically will limit how you can distribute or publish your own software. In particular, if your software is “based on” db4o software licensed under GPL terms, then GPL terms will apply to your software as well. db4objects takes a broad interpretation of the GPL. In our interpretation, there are many situations where your software will be “based on” db4o software, including but not limited to the following situations:

In all of these situations, if you distribute or publish your software, you will have to make available source code for your software, in addition to meeting other GPL requirements for your software.