Brian Hyndman is a market-maker in the most literal sense. As the senior vice president of Nasdaq OMX Group’s transaction-services division, the 41-year-old financial technology expert helped to establish ­Nasdaq OMX BX. Now he’s presiding over the launch this month of another new exchange — Nasdaq OMX PSX — that will be the first to place its emphasis not on the speed of trades but on their size.

“Buy-side investors have been frustrated that they couldn’t always get to the front of the line” because of the size of their trades, explains Hyndman. “Now they can put up a larger order and get a larger portion of incoming liquidity.” He hopes the new exchange will bring greater transparency and liquidity to public markets by attracting orders that would otherwise have gone to “dark pools” — alternative off-exchange venues where buyers and sellers can trade anonymously.