Owner or prospective owner of future copyright can assign either wholly or partially, generally or subject to limitations and either for whole or part of term of copyright. Assignments must be made in writing and signed by owner or duly authorised agent. Assignment can also be made by testamentary disposition and where unpublished work is disposed off by will, it is inferred that the copyright also passes unless a contrary intention is expressed to this effect. Copyright assigned in respect of unpublished work for specific purpose of publication reverts to owner if such work remains unpublished for a period of three years from date of assignment.