Market Overview

IEX Launches Free Web API


IEX, the Investors Exchange, launched a free, web-based API supplying
IEX quoting and trading data for mobile, desktop and trading
applications. As America's newest stock exchange, IEX trades U.S. equity
securities, including exchange-traded funds (ETFs).

"IEX is simply providing our Members their own information back to them
at no charge," said Brad Katsuyama, co-founder and CEO of IEX. "The role
of an exchange is simple: Members send orders to exchanges and exchanges
match orders into trades. Legacy stock exchanges obstruct transparency
and create an uneven playing field by overcharging for market data on
orders they did not create."

Accessible via web, IEX API 1.0 provides any individual or academic,
public or private institution looking to develop applications that
require stock market data to access near real-time quote and trade data
for all stocks trading on IEX. For the month of January, IEX matched an
average of 128 million shares – equivalent to more than $5 billion of
notional value – per day. On a typical day, IEX will trade more than
5,700 different stock symbols.

The IEX API will offer the following data at no cost to users:

  1. TOPS aggregates the best bid and offer for all stocks quoted on
    IEX's order book, and also provides data for trades on IEX, including
    price, size and time. For an example of an app that's using TOPS,
    see the IEX
    TOPS viewer app
  2. MARKET tracks industrywide equity trading volume. For an
    example of an app that's using MARKET, see the IEX
    Market Volume app
  3. STATS collects aggregate metrics, including volume, notional
    volume, routed volume and market share. For an example of an app
    that's using STATS, see the official IEX
    mobile app

No user-specific or identifying data is captured by IEX and none will be
made available via IEX API 1.0.

"The relevance of IEX market data increases as our market share grows.
So every order sent to IEX is a vote for a different type of stock
exchange: one geared towards better trading outcomes, not the sale of
data, access and speed," said Katsuyama.

Launched in September 2016, the Investors Exchange has earned
recognition for high execution quality, including the lowest effective
spread in more S&P 500 stocks than any other exchange. Technology
innovations including IEX's patent-pending "speed bump" and IEX's
patent-pending Discretionary Peg are designed to deliver the fairest
price to investors. IEX operates the only U.S. stock exchange without
the conflicts of rebates, co-location and proprietary data revenue

for more details on IEX API 1.0.

Read about our first four months as an exchange on the IEX blog:

IEX is the Investors Exchange: a fair, simple, and transparent stock
exchange dedicated to investor and issuer protection. Built on the
belief that every investor is entitled to the same right to trade on
equal terms on every single trade, IEX is on a mission to level the
playing field by eliminating unfair advantages from the markets.

On September 2, 2016, IEX launched as America's newest stock exchange,
and regularly matches over 100 million shares daily with a notional
value of over $5 billion. On February 21st, 2017, IEX reached a record
market share of 2.3% of total U.S. equity volume. IEX plans to begin
listing publicly-traded companies in 2017.

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