At-the-market offerings: how an ATM program works

An at-the-market offering is a registered sale of newly issued shares by a listed company, made into the existing trading market over time through a sales agent at prevailing prices. It is not an at-the-market order, which is a broker instruction to fill at the best available price, and it has nothing to do with cash machines.

Key takeaways

• An ATM program is a shelf takedown, not a placement. Rule 415(a)(4) permits a continuous registered offering into the trading market. Since the 2005 offering reforms there is no volume limit and no requirement to name an underwriter.
• Shelf eligibility is the gate. No effective shelf, no ATM program. Below US$75 million of public float the baby-shelf limit in General Instruction I.B.6 applies.
• Price is the market's, not yours. There is no negotiated discount, which is the attraction; the price is also whatever the book gives you that day.
• The agent uses efforts, not guarantees. Sales are made within parameters the issuer sets in a placement notice, and nobody is obliged to deliver a fill.
• The program stops more often than issuers expect. It is suspended around results and pending material developments, and Regulation M applies when another distribution is running.

What it is, and what it is not

The phrase "at the market" collides with two much larger populations of searcher, so be blunt about the difference. An at-the-market order is what an investor gives a broker: fill this now, at the best available price. An ATM in ordinary speech is a cash machine. Neither has anything to do with this page.

An at the market offering is a corporate financing. The issuer registers shares, appoints a broker-dealer as sales agent, and sells new shares into its own order book a slice at a time. No investor is identified, no block is negotiated, and no discount is agreed. The economics are the market price minus the agent's commission.

Who can run one

Sales are taken off a shelf registration statement, in practice on Form S-3, with a prospectus supplement filed under Rule 424. Rule 415(a)(4) is the provision that permits an offering to be made "at the market" into an existing trading market. The 2005 securities offering reforms removed the volume limitation and the requirement to identify an underwriter, which is why the structure became routine for small and mid-cap issuers.

Two limits bite. The first is capacity: an issuer with public float below US$75 million operates under General Instruction I.B.6, which caps primary sales at one-third of public float in any rolling 12-month period, and how a continuous program counts against that cap is a question for counsel before launch. Staff guidance moved in 2026, including Corporation Finance Interpretation 116.26 of 19 March 2026 on programs launched before a float measurement falls below the threshold. The second is liquidity: a program sells only what the order book absorbs, so average daily traded value sets the realistic size.

How the sales agent actually works

The relationship sits in a sales agreement, often called an equity distribution agreement, between the issuer and one or more broker-dealers. It sets the maximum aggregate amount, the commission, the representations and the conditions to each sale.

Selling is then driven by the issuer, which delivers a placement notice specifying how many shares may be sold, over what period, and the minimum price below which the agent must not sell. The agent sells on a commercially reasonable efforts basis within those parameters, and in some agreements may also purchase as principal under a separate written instruction. Trades settle one business day after the trade date in the United States. The issuer can suspend the program at any time, and does.

Disclosure and the quiet mechanics

The prospectus supplement filed at launch is the primary disclosure: it names the agent, the maximum amount and the manner of sale. The registration statement is kept current, including through the annual Section 10(a)(3) update, and sales are reported in the issuer's periodic reports rather than trade by trade.

Two constraints run continuously. The first is information: an issuer cannot sell into the market while holding material non-public information, so programs go dark around results and unannounced transactions. The second is Regulation M, which restricts bids and purchases by an issuer and by distribution participants during a restricted period, and has to be assessed whenever a buyback or another distribution overlaps.

ATM, PIPE transaction or equity facility

The three answer different questions, and the choice usually turns on whether the amount or the price matters more.

When an ATM program is the wrong tool

It fails on thin volume. Where average daily traded value is small, selling any meaningful amount either moves the price against the issuer or takes months, and the program becomes a visible overhang. It fails when the money is needed by a date, because nothing about it is committed. And it does nothing for an issuer that is not shelf-eligible, which is where a private placement by a public company or a registered direct offering returns to the table.

Elsewhere the tool exists under different rules: Canada runs at-the-market distributions under its own shelf regime and limits, and most other venues rely on placement capacity instead. Compare the United States and Canada pages before assuming a US structure travels, or send the float and the traded volume.

Related reading

• All instruments
• Rule 144 explained
• Dilution mechanics
• Who we fund

Primary sources

• eCFR — 17 CFR 230.415, Rule 415(a)(4) (at the market offerings)
• eCFR — 17 CFR 230.424, Rule 424 (filing of prospectuses)
• U.S. Securities and Exchange Commission — Form S-3 and its General Instructions
• SEC Division of Corporation Finance — Securities Act Forms interpretations
• eCFR — 17 CFR 242.102, Regulation M Rule 102 (issuers and selling security holders)

At-the-market offerings: frequently asked questions

What is an at the market offering?

It is a registered offering in which a listed company sells newly issued shares into the existing trading market over time, through a sales agent, at whatever price the market is paying. Nothing is priced in advance and nothing is placed with an identified investor. The buyer is whoever is on the other side of the order book.

Is an ATM offering the same as an at-the-market order?

No, and the two get confused constantly. An at-the-market order is a trading instruction given by an investor to a broker to execute at the best price currently available. An at-the-market offering is a corporate financing in which the issuer creates and sells new shares. One is a way to buy stock that already exists; the other is a way to create stock that does not.

Does an issuer need an effective shelf to run an ATM program?

Yes. Sales are made off a shelf registration statement, in practice on Form S-3, with a prospectus supplement filed for the program. An issuer that is not shelf-eligible cannot run one, and an issuer whose public float is below US$75 million can, but has to work within the one-third of public float limit in General Instruction I.B.6.

How is an ATM program different from a PIPE transaction?

An ATM program sells at market prices to anonymous buyers over weeks or months and gives no certainty of amount. A PIPE transaction sells a fixed amount to identified investors at a negotiated price, usually at a discount, and settles on a date. An issuer that needs a specific sum by a specific day is choosing the wrong tool.

Can an issuer sell under an ATM program while it holds material non-public information?

No. Selling into the market while in possession of material non-public information is exactly the exposure the securities laws are aimed at, which is why programs are suspended around results and whenever a material development is pending. Regulation M restricted periods also have to be considered where another distribution of the same securities is running.