This document discusses cost-effective and anonymous data sharing using forward secure identity-based ring signatures. It proposes a new notion of forward secure ID-based ring signatures that allow ID-based ring signature schemes to provide forward security. This is the first scheme to provide this feature for ring signatures in an ID-based setting. The scheme provides unconditional anonymity and can be proven to be forward-securely unforgeable in the random oracle model under the RSA assumption. It is efficient, requiring only one exponentiation for key updates and no pairings. This scheme enables authentic and anonymous data sharing in large-scale systems like smart grids.