Consolidated Tape Association

The Consolidated Tape Association (CTA) oversees the dissemination of real-time trade and quote information (market data) in (NYSE) and (AMEX) listed securities ( and bonds). It is currently chaired by Emily Kasparov of the Chicago Stock Exchange, the first woman and the youngest chair elected to the position.

CTA manages two Plans to govern the collection, processing and dissemination of trade and quote data: the Consolidated Tape Plan, which governs trades, and the Consolidate Quotation Plan, which governs quotes. The Plans were filed with and approved by the Securities and Exchange Commission (SEC) in accordance with Section 11A of the Securities Exchange Act of 1934.

Since the late 1970s, all SEC-registered exchanges and market centers that trade NYSE or AMEX-listed securities send their trades and quotes to a central consolidator where the Consolidated Tape System (CTS) and Consolidated Quotation System (CQS) data streams are produced and distributed worldwide. The CTA is the operating authority for CQS and CTS.

The current Participants include:

The New York Stock Exchange is the Administrator of Network A, which includes NYSE-listed securities, and the American Stock Exchange is the Administrator of Network B, which includes AMEX-listed securities.

CTS and CQS receive trade and quote information, respectively from NYSE, AMEX, and the other using a standard message format. Each system validates its respective message format, verifies the information against its databases (e.g., valid symbol, etc.), consolidates the information with the other market centers' information, and disseminates the information to the data recipients in its respective common standard message format via the IP Multicast network. Included in every trade and quote message is a timestamp which represents the time that the message is disseminated.

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