There is no open source software dedicated to contract management. Nevertheless, many open source ECM solutions can be used for such case due to their low cost and great versatility.
For pure contract management, we would recommend Alfresco or Nuxeo 5.
LEADING OPEN SOURCE DMS SOLUTIONS USABLE AS CONTRACT MANAGEMENT SOLUTIONS
Alfresco is the first open source enterprise-scale document management system that includes a modern content repository, an out-of-the-box portal framework for managing and using content designed to work with standard portals, and a Common Internet File System (CIFS) interface that provides Microsoft Windows file system compatibility. Alfresco takes the lessons of building document management systems for the last 15 years and applied them to build an open source content management system that is easier to use, more scalable and more adaptable.
Maarch is an Open Source framework for archiving and retrieving large volumes of static documents. In a certain way, it is designed as an IDARS product (Integrated Document Archiving and Retrieval System).
Nuxeo is a standards-based, open source platform for building ECM and DMS applications. Its component-based and service-oriented architecture makes it easy to customize and extend, making developers more efficient and ultimately, happier.
OTHER OPEN SOURCE DMS SOLUTIONS USABLE AS CONTRACT MANAGEMENT SOLUTIONS
xinco™ DMS is a powerful Web-Service based Information and Document Management System (DMS) for files, text, URLs and contacts, featuring ACLs, version control, full text search and an FTP-like client. xinco DMS™ is a powerful Web-Service based Information and Document Management System (DMS) for files, text, URLs and contacts, featuring ACLs, version control, full text search and an FTP-like client.
Kimios DMS provides a fully Open Source DMS. Designed for organisations of any size and any activity, Quotero is pretty fast and with interesting features like an Office plugin. Even if Quotero is pretty young compared to Alfresco or Nuxeo, it is a promising open source DMS.
LogicalDOC is an enterprise electronic document management system, which, due to its characteristics, can be used by large companies as well as by the small ones, as a useful tool in knowledge management processing, providing a more flexible and lower-cost alternative to other proprietary applications.