Apache Software License

Apache License

The Apache Software Foundation logo
Author	Apache Software Foundation
Latest version	2.0
Publisher	Apache Software Foundation
Published	January 2004
DFSG compatible	Yes
FSF approved	Yes
OSI approved	Yes
GPL compatible	Yes – version 2.0 is compatible with GPL v3, but 1.0 & 1.1 are incompatible.
Copyleft	no
Linking from code with a different license	yes
Website	www.apache.org/licenses

The Apache License, Version 2.0 (ALv2) is a permissive free software license written by the Apache Software Foundation (ASF). The Apache License requires preservation of the copyright notice and disclaimer. Like other free software licenses, the license allows the user of the software the freedom to use the software for any purpose, to distribute it, to modify it, and to distribute modified versions of the software, under the terms of the license, without concern for royalties. This makes ALv2 a FRAND-RF license. The ASF and its projects release the software they produce under the Apache License and many non-ASF projects are also using the ALv2.

A free software license is a notice that grants the recipient extensive rights to modify and redistribute that software. These actions are usually prohibited by copyright law, but the rights-holder (usually the author) of a piece of software can remove these restrictions by accompanying the software with a software license which grants the recipient these rights. Software using such a license is free software (or free and open source software) as conferred by the copyright holder. Free software licenses are applied to software in source code as also binary object code form, as the copyright law recognizes both forms.

The Apache License 1.1 was approved by the ASF in 2000: The primary change from the 1.0 license is in the 'advertising clause' (section 3 of the 1.0 license); derived products are no longer required to include attribution in their advertising materials, but only in their documentation.

The ASF adopted the Apache License 2.0 in January 2004. The stated goals of the license included making the license easier for non-ASF projects to use, improving compatibility with GPL-based software, allowing the license to be included by reference instead of listed in every file, clarifying the license on contributions, and requiring a patent license on contributions that necessarily infringe a contributor's own patents.