bitcoin-op-return

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Conclusions
Bitcoin’s long-running debate over acceptable uses of the block chain has received some much needed clarity. Applications can now inexpensively add a 40 byte data payload to transactions using the OP_RETURN script function. On a technical level, OP_RETURN doesn’t enable anything that wasn’t previously possible. Instead, OP_RETURN provides a standard interface through which new services can potentially be layered onto the block chain, and a central point of focus for future work on integration tools.

This move brings the vision of Bitcoin as a universal platform for mediating complex agreements one step closer to reality. The extent to which the Bitcoin community will embrace this vision remains an open question.