Relationship among copyright holders for use and reuse of digital contents

Modification and reuse of digital contents, particularly web data, has become easy due to advancement in computer technology. The work created by a person (or a group of persons) can be reused by another person (or group) for different purpose. Thus, there can be multiple copyright holders for the same information. In such scenario, it is important to define the relationship among the copyright holders. There have been some attempts at designing the Electronic Copyright Management System (ECMS) \cite{6,7}. However, this system is used for defining and registering the information of one copyright holder. Another attempt to develop copyright management systems is reported in \cite{indecs}. The key feature of this system is that they have an RDF expression for copyright metadata. When multiple creators take part in creating one content or when contents are created reusing existing contents, it is vital to define the relationship among copyright holders. This relationship should be clarified in order to make proper allocation of profits and protect rights of all the copyright holders. Therefore, a framework is required where the relationship among copyright holders and profit allocations are described. In this paper we outline the main points of such framework. We refer the readers to see \cite{tr-wmu} for a detailed description. The proposed framework also represents copyright processing for multiple rights holders, it gives a framework for realizing transaction systems where reuse for creating new contents is promoted. In this paper we also outline the conceptual model designed for describing copyright information, examining the relationship among rights holders, and modeling charge rules.