0x Labs, the firm behind blockchain infrastructure development protocol 0x, has announced that it has closed a $70 million Series B in an investment round led by Greylock, a key industry player in blockchain project investments. The recently closed Series B funding round also saw the participation of Pantera Capital, A.Capital, Jump Capital, Sound Ventures, OpenSea, Coinbase, Brevan Howard, Reid Hoffman, and Jared Leto.