At the heart of this exchange is a saitori, who is an intermediary. The saitori maintains a public limit order book and is obligated to intervene in the market (and halt trading), if necessary, to...

At the heart of this exchange is a saitori, who is an intermediary. The saitori maintains a public limit order book and is obligated to intervene in the market (and halt trading), if necessary, to ensure that there would be minimum volatility in the prices of stocks.