This paper proposes energy scheduling mechanism that establishes competitive market among multiple prosumer microgrids. Prosumers based on the their role will be able to acquire production points (PP) for being a seller or consumption points (CP) for buying energy in the market. Contributions of each individual microgrid are recorded by noval contribution metric (CM) concept. Transactive energy is scheduled in such way that prosumers with higher CM will benefit more, thereby encouraging network users to contribute more and consume less energy. Truthful bidding principle of Vickrey auction is applied to prevent overbidding and underbidding to maintain market in fair state. Blockchain was used to enhance trust between prosumers and shift the market to decentralized state. Strategies to integrate Locational Marginal Pricings (LMPs) into the system were proposed in the paper. The system was simulated using 5 microgrids in IEEE37-bus feeder. Results showed effectiveness of CM based mechanism to manage energy scheduling.