Apache License - Version 2.0
By
Dr. Kalyan C. Kankanala

The Apache Software Foundation makes some of its softwares available under the Apache License. The latest version of the Apache License is compatible with GPL and may be used by any person for contributing open source software. Some of the softwares governed by the Apache License include Tomcat, Lucene, Roller, Velocity and so on.

Rights

The following copyrights are granted over the software by the license:

Right to reproduce;
Right to prepare Derivative Works;
Right to publicly display;
Right to publicly perform;
Right to sublicense; and
Right to distribute

The following patent rights are granted over the software by the license:

Right to make;
Right to have made;
Right to use;
Right to offer to sell;
Right to sell; and
Right to import

As per the license, the patent license will terminate, if the recipient institutes patent litigation with regard to the software under the license.

Distribution conditions

The license allows the recipient of software under the license to distribute the original software or the modified version of the software in the form of object or source code provided the following conditions are satisfied:

a. A copy of the license is given along with the distributed software;
b. Notice of modifications is provided;
c. All copyright, trademark, patent and attribution notices are retained; and any attribution notices relating to the derivative work are added.

The modified version of the software may be distributed with a different copyright statement and under different license terms and conditions provided those terms and conditions are compliant with the Apache License.

Other Provisions

As per the license, the trademarks of the licensor should not be used by any person for any purpose. The license does not give any warranty relating to the software. Furthermore, the licensor is not liable for any damages relating to the software. However, the recipient of the software may accept additional warranty or liability. But in such a case, the recipient should indemnify the licensor of the software.