Digital signatures achieved through public key cryptography work for individual users. They do not have features such that they can be used for multiple documents or multiple users. Signatures with homomorphic property are designed for this purpose. Yet, most of the homomorphic signatures pertain to signature of an algorithm thus providing verifiability that the algorithm has been executed over a set of inputs. There is still need of homomorphic signatures in which only the signatures have homomorphic properties that can be used to concatenate or combine multiple signatures. Such malleability, though desirable, may have vulnerability towards forging or other attacks. So a homomorphic signature has to suffice both conditions: meet the malleability requirements of the application and be secure against attacks.