NASDAQ OMX PSX (PSX)

NASDAQ OMX Group

NASDAQ OMX PSX (PSX)

PSX, NASDAQ OMX's third US equity trading platform, trades Reg NMS securities listed on NASDAQ, NYSE, NYSE Arca, NYSE Amex and other regional exchanges. At its launch in 2010, the exchange was the first US equity trading platform to operate a price-size priority model. PSXis powered by INET technology.

Pending SEC approval in 2013, NASDAQ OMX plans to reintroduce PSX with a price-time execution model and a focus on exchange-traded products (ETPs). Migration to a price-time execution model is intended to encourage broader participation and more robust quoting across available securities.

Price-time priority means that displayed limit orders will be ranked for execution first by price level; orders at the same price will then be ranked based on their time of entry into the system. Non-displayed shares will be executed after displayed shares at the same price in the order in which they are received.

PSX will introduce Registered Market Maker (RMM) status in all securities; RMMs must maintain a continuous, two-sided quote of at least one round lot during regular market hours for each security in which they are registered.

PSX trades clear on the Regional Trade Interface Operations (RIO) contract sheet. This trade capture and reporting service offered by the National Securities Clearing Corporation (NSCC) and available to all qualified NSCC members provides for the processing of domestic equity and corporate bond transactions from the regional markets as well as exercise and assigned options and expired single stock futures from the Options Clearing Corporation (OCC).