Market Data for a Trading App or Terminal: A Data Vendor, Direct Exchange Feeds or Your Broker's Data

The prices in a trading app or terminal come from one of three places: your partner broker's data, a market data vendor that collects many exchanges' feeds, or each exchange directly. Market data means the prices and trades an exchange publishes as trading happens. For some products it includes the full order book, the list of all orders waiting to trade. On every route, the exchange that produced the prices usually sets the licence terms and fees for using them. The bill depends mostly on who sees the prices and how fresh they are. Showing prices to your clients counts as passing the data on, which brings agreements and monthly reports of its own.

What exactly are we paying for when we pay for market data?

An exchange publishes market data as a feed, a continuous stream of quotes and trades. A basic feed carries the best bid and offer for each instrument, the highest price a buyer will pay and the lowest a seller will accept, plus the last trade. A depth feed adds the orders waiting at other prices, which together make up the order book. Delayed data reaches the user after a fixed wait, such as 15 minutes.

Exchanges sell market data under licence, and the licence terms usually apply whoever delivers the data. Databento, a market data vendor, says in its live data guide, read on 19 October 2026: “Each venue defines subscriber statuses, use cases, device counts, and their corresponding license fees differently.” A venue is any place where trading happens, and a device is roughly one screen or terminal. The examples below are from the US and the EU.

Can we start with our partner broker's prices?

A partner broker's prices are often the simplest start. Your app reads them from the same broker it sends orders to, through the broker's API, the interface your software uses to talk to the broker's systems. The limits are coverage and licence: a broker's data plan may leave out some markets or the full order book, and its real-time prices may come from a single exchange.

Alpaca, a US brokerage whose Broker API lets other companies build their own trading apps on top of it, is one example. Its market data page, read the same day, offers those companies “tiered subscription plans designed for higher-volume, multi-user platforms.” A note under the plans says: “similar to the free plan all the standard plans are real time IEX or 15 mins delayed SIP.”

IEX is one US stock exchange. SIP stands for securities information processor, the system behind the US consolidated tape, the combined feed of every US stock exchange. In Alpaca's standard plans, the real-time prices come from one exchange and may differ from the best price in the whole market, which arrives 15 minutes late. The same page offers custom pricing when none of the listed plans suits a company's app.

Before you build on a broker's data, get two answers in writing: whether the broker's data licence lets your app show the prices to clients, and who reports your users to each exchange.

What does a market data vendor take off our hands?

A market data vendor, sometimes called an aggregator, delivers many exchanges' data in one format under one contract, so your developers connect to the vendor alone.

Even with a vendor, you may still need the exchange's own licence. Databento's guide says most commercial users without an existing licence “will need to apply for a direct license agreement with the venue before they can access live data on Databento or via any other data vendor.”

Part of the reporting can move to the vendor. For certain venues and use cases, Databento says it will “operate as a vendor of record (VoR) and report your devices under our license agreement”.

When is it worth connecting to an exchange directly?

Connecting to an exchange directly can pay off in the few markets where your clients or your own trading need full depth or the fastest prices. For the other markets, compare a direct feed, including the staff to run it every trading day, with a vendor's price for the same data.

A direct feed comes from the exchange itself, with full depth where the exchange offers it and no extra step through a vendor. For each exchange, going direct means a data agreement, the exchange's fees for direct access, a network connection and software that reads the exchange's own message format.

The software that reads a feed is called a feed handler. It rebuilds the order book from a stream of small messages and recovers when a message goes missing. Ask each exchange how it announces changes to its feed format, because a format change usually means work on the handler.

What makes the data bill go up or down?

Exchange fees often depend on each user's status: professional or non-professional. A non-professional is, broadly, a private person investing their own money. The fee page of the US consolidated tape, read the same day, lists today's monthly fees. For shares listed on the New York Stock Exchange, the professional fee is “$45 / $27 / $23 / $19 per device”, tiered by the number of devices, and a non-professional pays a “Flat $1.00 per person per Tape”. A tape is the consolidated feed for one group of listed shares.

The US consolidated tape moves to the CT Plan, a new rulebook for its fees and policies, on a date its FAQ gives as “currently planned for April 1, 2027.” Under the CT Plan, the fee page lists a flat $26 per professional for the same shares and a “Sliding scale from $0.90 down to $0.25” for non-professionals. The FAQ also says the new policy “classifies the use, not the person”, so one person can count as a professional at work and a non-professional at home.

Delayed data and software use change the bill too. Under the CT Plan's fee schedule, “Delayed and end-of-day redistribution is not fee liable on any Tape but still must be explicitly licensed.” Use of prices by software alone, with no person watching a screen, is called non-display use. Databento's fee table shows some venues charging a separate fee for it.

What changes when our clients see the prices?

Showing exchange prices to clients is redistribution: your company passes the data to people outside it. Databento's guide calls this distribution and gives “displaying real-time quotes on a customer-facing web app” as an example. Under the CT Plan, “firms that pass it on to others execute the Distribution Agreement”. Depending on the route, your broker or vendor may hold the agreement that covers your clients, or your company signs one itself.

Redistribution brings counting and reporting. Under the CT Plan, “Reports are due no later than the 15th calendar day after month-end”. Records of access, use, distribution and reporting must be “retained for no less than three years.” The policies page describes today's audit clauses as “CPA-certified device-count reports at the vendor's expense”: device counts certified by an outside accountant, paid for by the firm passing the data on.

To follow the exchanges' terms, your app needs an entitlement system: the part that decides which user may see which exchange's data, in real time or delayed. It usually has these parts:

• A sign-up step that records each client's status. The CT Plan uses “one standard attestation of just six questions”, a short questionnaire each client confirms. Keep the answers: the FAQ ties a firm's good-faith protection to clients' answers that are “retained and producible.”
• A check behind every price screen and API response, so each user sees only the exchanges and depth they are licensed for
• Delayed prices marked as such. The tape's FAQ says “every display must be clearly labeled as delayed with the delay period stated.”
• A monthly count of users per exchange and status, in each exchange's or vendor's format
• Records of who had access to what, kept as long as each agreement requires

Are the rules different for EU and crypto exchanges?

In the EU, MiFIR, the regulation on markets in financial instruments, sets rules for selling market data. Its Article 13, rewritten in 2024 by Regulation (EU) 2024/791, requires trading venues and some other firms that publish such data to offer it “on a reasonable commercial basis, including unbiased and fair contractual terms”. Fees must be based on “the cost of producing and disseminating the information” plus “a reasonable margin”.

MiFIR's Article 13 also requires venues to make the data available “free of charge 15 minutes after publication in a format that is machine-readable and usable for all users, including retail investors.” Real-time data can still carry fees. Ask each EU venue, or your vendor, on what terms your app may show the free delayed data.

Crypto exchanges often publish prices through public APIs, which can make the data look free to use. Each exchange's API terms decide whether an app may show those prices to clients. Coinbase's Market Data Terms of Use, last updated on 7 August 2026, say the data “may not be used to build an application intended for use by end users other than for you or your officers/employees.” Without Coinbase's “prior express written consent”, you may not “Redistribute, display, or disseminate the Market Data” outside your organisation.

What stays ours if we change the data source?

A design that keeps the source replaceable converts every feed into your own internal format. Each source gets an adapter, a small piece of code that translates that source's messages, so screens, charts and risk checks never read a source's format directly. A new source then means a new adapter.

Keep your own list of instruments, with one record per instrument that holds the code each source uses for it. The article on multi-asset terminals, linked above, explains that list in more detail. Agree on these points before you sign with any data source:

• Whether clients may see the prices, in real time or delayed, and in which countries
• Who reports your users to each exchange, and who pays for a wrong report
• How audits work and how far back they can go
• The notice period, and how long data keeps flowing after notice
• Whether you may keep stored price history, and for what use

What should we ask an engineering firm about market data?

Send every engineering firm the same questions:

• Which exchange, vendor or broker feeds have you connected in a system that runs in production today, and who held the data licence?
• How will our system decide which user sees which exchange's prices, in real time or delayed?
• Which part of the system will count users for each exchange's monthly report, and how can we check that count before an audit?
• If we change data source in two years, which parts of the code change?
• What happened the last time a feed you support changed its format?

A firm that has run trading systems in production can name the feeds and describe an incident it handled. If the answers stay general, ask for a client reference you can call.

Where does amBrain fit?

amBrain builds algorithmic trading infrastructure: order execution, market data and pre-trade risk controls. One line on amBrain's website reads: “Trading terminal development, order management systems, and FIX protocol exchange integration.”

amBrain has been building software since 2019. It works in three formats: full delivery, a dedicated team, or engineers embedded in your team. Its line on ownership is “The client keeps full ownership of the product and the code, except our reusable components.” Ask for the list of those components by name before you sign. If amBrain is on your shortlist, give it the same questions as any other firm.

This article is not a case study and describes no client work. It does not say that amBrain has built a multi-asset terminal or an entitlement system, or connected any feed described here. Nor does it say that amBrain holds a data licence, exchange agreement or vendor contract for itself or a client. Alpaca, Databento, Coinbase and the US consolidated tape are examples from their own published pages, and the article claims no relationship between amBrain and any of them or any exchange it names. It gives no amBrain prices or timelines and is not legal advice: data rules differ by exchange and country, so check them with each exchange and, where needed, a lawyer.