The Common Public License (CPL) is an open source license agreement released by IBM. The company holds copyright over the license. It permits the distribution of the license but limits the right to modify it. Softwares such as Windows Installer XML developer tool, Windows Template Library and so on have been released under the Common Public LIcense.

Rights

The agreement grants a license over the following rights under the copyright law to every person receiving a software under the license:

Right to Reproduce;
Right to Distribute (source code or object code);
Right to Make derivative works;
Right to Publicly display;
Right to Publicly perform; and
Right to Sublicense the software.

The license grants the following patent rights over the software made available under the license:

Right to make;
Right to use;
Right to sell;
Right to offer to sell;
Right to import; and
Right to transfer the work in object or source form.

Conditions for distribution

A person may distribute a software in the form of source code provided

a. The software is distributed under the common public license agreement;
b. a copy of the license is included with each copy of the software;
c. The copyright notices in the software are kept intact; and
d. A person contributing the software or modifying the software indicates that he is the author.

A software available under the license may be distributed in object form by any person in accordance with the following conditions:

a. All terms and conditions of the common public license are satisfied;
b. The software may be distributed under a different license provided the license,

 i. disclaims all warranties;
 ii. excludes the person providing the software under the Common Public License    from liability for damages;
 iii. states that the additional terms are provided by the distributor; and
 iv. gives information about availability and access of the software.

Commercial Distribution

Any person receiving the software under the license may distribute it for commercial purposes. In case of such a distribution, the license agreement provides that the person distributing the software will be liable to indemnify the person who contributes the software under the license for any losses or damages arising out of the distribution.

No liability

The person providing a software under the license is not liable for any losses or damages arising out of distribution of the software. The license states that any person receiving a software under the agreement will be solely liable for infringement of Intellectual Property rights of a third party. As per the license, the person providing a software under the license undertakes no liability for any such infringement. The person receiving the software should take necessary steps to acquire any licenses required for the purpose.

No Warranty

As per the license, any person contributing a software under the license does not provide any sort of warranty over the software.

Patent Litigation

If any person receiving a software under the license files a suit against the person, who contributed the software, the rights granted under the license will stand terminated.

Revision

The license agreement may be modified and revised only by IBM and no other party has the right to modify and distribute new versions of the license.