Exercise or Conversion of Derivative Securities: Section 16 and Form 4

When an insider exercises a stock option or converts a warrant into common stock, SEC rules on the exercise or conversion of derivative securities treat that event as a non-event for short-swing profit purposes under Rule 16b-6, while still requiring a Form 4 filing within two business days and leaving the newly acquired shares fully exposed to Section 16(b) matching, Rule 144 resale limits, and public disclosure of any filing failure.¹ The exemption protects the mechanics of exercising; it does nothing for what you do with the shares afterward.

Who These Rules Apply To

Section 16 covers three groups: directors of the issuer, officers of the issuer, and anyone who beneficially owns more than ten percent of a registered class of the company’s equity securities.² “Officer” is a functional test. It reaches the president, principal financial officer, principal accounting officer or controller, any vice president in charge of a principal business unit or function, and anyone else performing a policy-making role, regardless of formal title.³

Ten-percent beneficial ownership is measured using the same tests that apply to Schedule 13D reporting.⁴ Once you fall into any of the three categories, everything that follows applies.

What Counts as a Derivative Security

A derivative security is any option, warrant, convertible security, stock appreciation right, or similar instrument with an exercise or conversion privilege at a price related to an equity security, and any instrument whose value derives from the value of an equity security.³

Several things are carved out: pledgee rights to sell collateral, pro-rata rights arising from mergers or exchange offers, broad-based index options and futures, and interests in employee benefit plans. Two exclusions matter directly to an insider exercising options. Rights to surrender shares to cover the exercise price or satisfy tax withholding are not themselves derivative securities, and rights without a fixed exercise price are excluded entirely.³

Why the Exercise Itself Is Exempt

Rule 16b-6(b) exempts the closing of a derivative security position through exercise or conversion from Section 16(b) short-swing profit liability. It also exempts acquiring the underlying shares at a fixed exercise price when you exercise a call-equivalent position.¹

The reasoning: the investment decision and economic exposure were fixed when the option was granted, so paying the pre-set strike price to convert the option into stock is not a new investment decision the short-swing rule needs to police. The grant, if made under a Rule 16b-3-compliant plan (board approval, non-employee-director committee approval, shareholder approval, or a six-month holding period), was itself exempt.⁵ Exercise closes the loop.

The Out-of-the-Money Exception

Exercising an out-of-the-money option, warrant, or right is not exempt unless the exercise is necessary to comply with the sequential exercise provisions of the Internal Revenue Code.¹ Exercising an underwater option is uncommon, and the SEC treats it as suspect because the ordinary economic rationale doesn’t apply.

Share Withholding at Exercise

Companies routinely withhold shares at exercise to cover the strike price or tax obligations. Because the insider is technically handing shares back to the issuer, the withholding looks like a disposition. Rule 16b-3(e) exempts dispositions to the issuer from short-swing liability, provided the terms are approved in advance by the board or a committee of non-employee directors.⁵

If the original grant resolution already specified the exercise and withholding mechanics, no separate approval is needed when the withholding actually happens. If it didn’t, the withholding is a non-exempt disposition that can match against any purchase within six months to generate short-swing profit liability. This is a common failure point at companies where equity-award paperwork was drafted before someone thought carefully about Section 16.

What Section 16(b) Still Reaches

The exemptions cover the grant, the exercise, and (with proper approval) the withholding. They do not cover what most insiders actually want to do next: sell the shares.

Section 16(b) requires disgorgement to the company of any profit an insider realizes from matching a purchase and a sale (or a sale and a purchase) of the company’s equity securities within any six-month window.² Liability is strict. Intent is irrelevant. Whether you actually had inside information is irrelevant.

The trap for option exercises is that a non-exempt purchase in the six months before or after your sale can still match against that sale. A recent open-market buy, a non-exempt withholding, an out-of-the-money exercise, a share purchase through an employee stock purchase plan that doesn’t fit an exemption: any of these can pair with a sale of the exercised shares. The exercise itself doesn’t count as the “purchase” for matching purposes, but the sale of the underlying shares absolutely counts.

Section 16(b) is not enforced by the SEC. The issuer can sue, and if it fails to act within 60 days of a written demand, any shareholder can sue on the company’s behalf. A network of plaintiffs’ attorneys monitors filings and sends demand letters when the math looks favorable.

Reporting the Exercise on Form 4

The exercise is exempt from Section 16(b). It is not exempt from reporting. Section 16(a) requires you to disclose any change in beneficial ownership on Form 4, filed electronically, within two business days of the transaction date.⁶

Two business days is tight. Exercise on Monday, file by close of business Wednesday. The form must state the nature of the transaction, the number of securities involved, and for derivative securities the exercise price and expiration date.

If you’re newly appointed as a director, officer, or ten-percent owner, your first filing is Form 3, due within ten days, reporting all existing holdings including derivative securities. Form 5 is an annual catch-up for a narrow category of deferrable items (small acquisitions under $10,000 in a six-month period, gifts received) due within 45 days after fiscal year end.⁶ Almost everything belongs on Form 4.

The Transaction Codes for an Exercise

Each line on Form 4 carries a letter code. A wrong code can mischaracterize the exemption you’re claiming. The codes an insider will encounter when exercising:⁷

A: grant or award under Rule 16b-3(d), used for the original compensatory grant.
M: exercise or conversion of a derivative security exempt under Rule 16b-3, the standard code for exercising employee stock options.
F: payment of exercise price or tax liability by delivering or withholding securities incident to exercise or vesting under Rule 16b-3.
D: disposition to the issuer under Rule 16b-3(e).
X: exercise of an in-the-money or at-the-money derivative security outside the Rule 16b-3 exemption.
S: open-market or private sale of the underlying shares.

A cashless exercise typically shows up as an “M” line on the derivative security table (the option position closing) alongside an “S” or “F” line on the non-derivative table (the sale or the tax withholding). Analysts and plaintiffs’ counsel read these codes on EDGAR to spot potential short-swing violations.

Filing Through EDGAR

All Section 16 forms must be filed electronically through EDGAR.⁸ As of September 2025, all filers must comply with EDGAR Next, which replaced the older passphrase and password system.⁹

You need a CIK (Central Index Key, a permanent public identifier), a CCC (an eight-character CIK Confirmation Code containing at least one number and one special character), Login.gov individual account credentials, and authorization in the appropriate role.⁹ Set this up before you ever have a transaction to report. The two-business-day clock does not pause for credentialing problems.

Filings submitted by direct transmission on or before 10:00 p.m. Eastern time on a business day are deemed filed that day.⁸ There is no hardship exemption allowing paper filing of Forms 3, 4, or 5. The SEC posts each filing on a publicly accessible website by the end of the next business day.²

Rule 144 and When You Can Sell

Section 16 tells you what to report and what liability attaches. Rule 144 tells you when you can legally resell the shares. If the issuer has been a reporting company for at least 90 days, the minimum holding period is six months from the later of the acquisition date or the date the securities were acquired from the issuer or an affiliate. For non-reporting issuers, the period is one year.¹⁰

For cashless exercises, the holding period tacks back to the original option acquisition date, so shares acquired at exercise are treated as held since the option was received.¹⁰ For employee stock options that carry no investment risk, the holding period starts at exercise, not at grant, as long as the full purchase price was paid at exercise. That distinction can add months before a sale is clear under Rule 144.

What Happens If You File Late

The SEC periodically runs enforcement sweeps against late Section 16 filers. In September 2024, the agency settled charges against 23 entities and individuals for filing failures, with total penalties exceeding $3.8 million. Individual civil penalties in that sweep ranged from $10,000 to $200,000.¹¹

Beyond fines, the issuer must disclose in its proxy statement and Form 10-K the names of any directors, officers, or ten-percent owners who missed a Section 16 deadline during the most recent fiscal year, along with the number of late reports and the number of transactions not timely reported. The reputational hit from the proxy disclosure often outweighs the monetary penalty.

1
eCFR. 17 CFR 240.16b-6 – Derivative Securities
2
Office of the Law Revision Counsel. 15 U.S. Code 78p – Directors, Officers, and Principal Stockholders
3
eCFR. 17 CFR 240.16a-1 – Definition of Terms
4
eCFR. 17 CFR 240.16a-2 – Persons and Transactions Subject to Section 16
5
eCFR. 17 CFR 240.16b-3 – Transactions Between an Issuer and Its Officers or Directors
6
U.S. Securities and Exchange Commission. Insider Transactions and Forms 3, 4, and 5
7
U.S. Securities and Exchange Commission. Ownership Form Codes
8
U.S. Securities and Exchange Commission. Mandated Electronic Filing and Website Posting for Forms 3, 4 and 5
9
U.S. Securities and Exchange Commission. Understand and Utilize EDGAR CIK and CIK Confirmation Code (CCC)
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eCFR. 17 CFR 230.144 – Persons Deemed Not To Be Engaged in a Distribution
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U.S. Securities and Exchange Commission. SEC Levies More Than $3.8 Million in Penalties in Sweep of Late Beneficial Ownership and Insider Transaction Reports