Technologies are shown for secure management of evaluation data that involves receiving an evaluation value signal from a source, the evaluation value signal relating to an evaluation entity having an evaluation score secured on an evaluation data blockchain and verifying whether the source is identified in trusted source data. If the source is trusted, then the technology involves obtaining a weight associated with the source, obtaining the evaluation score for the evaluation entity from a first evaluation data block in the evaluation data blockchain, where the first evaluation data block is a most recent evaluation data block in the evaluation data blockchain, calculating a new evaluation score based on the evaluation score obtained from the first evaluation data block and the received valuation signal weighted according to the weight associated with the source, and securely committing the new evaluation score to the evaluation data blockchain in another evaluation data block.