SEC Rule 10b-5: What the Anti-Fraud Rule Actually Prohibits

SEC Rule 10b-5 makes it illegal to defraud anyone in connection with buying or selling a security: lying about a material fact, staying silent about one when you have a duty to speak, or running any other scheme to deceive. It is not a filing requirement and it does not name insiders specifically; it is the broad anti-fraud rule that insider trading cases, and a lot of securities fraud litigation generally, are built on. This guide covers what the rule actually says, how it differs from the mechanical reporting insiders already do on Forms 3, 4 and 5, and how the newer Rule 10b5-1 trading plan checkbox on those forms shows up in real data.

What Rule 10b-5 actually says

Rule 10b-5 was adopted in 1942 under the authority of Section 10(b) of the Securities Exchange Act of 1934, which itself only bars the use of a "manipulative or deceptive device" in a way the SEC's rules prohibit. The rule fills in that authority with three clauses, and it is unlawful for any person, directly or indirectly, in connection with the purchase or sale of any security, to:

1. Employ any device, scheme, or artifice to defraud.
2. Make an untrue statement of a material fact, or omit a material fact necessary to make other statements not misleading, in light of the circumstances.
3. Engage in any act, practice, or course of business that operates as a fraud or deceit.

It is now codified at 17 CFR 240.10b-5, and courts have treated the ordinary dictionary meaning of "device," "scheme" and "artifice" as the baseline for reading the first clause: something devised by design, a plan, and an artful trick, respectively.

Who the rule applies to

Unlike Section 16 of the Exchange Act, which specifically targets officers, directors and 10% owners, Rule 10b-5 is written to cover "any person." That is deliberately broader than company insiders: it reaches anyone committing fraud in connection with a securities transaction, including outside parties who trade on information they were not entitled to use. Insider trading cases are the best known category of Rule 10b-5 enforcement, but the rule's text is not limited to them.

What makes a trade a Rule 10b-5 problem for an insider specifically is usually the combination of a duty (to the company or its shareholders) and a material fact the trader had and the public did not. That duty-based theory is why insider trading is treated as a form of fraud under 10b-5 rather than as its own separately defined offense in the rule's text.

Rule 10b-5 versus Forms 3, 4 and 5

It helps to keep two different legal mechanisms apart:

A transaction can be reported correctly and on time on a Form 4 and still raise a Rule 10b-5 question if the person trading had undisclosed material information at the time. Conversely, a late or missing Form 3 or Form 4 is a separate, narrower problem under Section 16, not automatically a 10b-5 violation. For the mechanics of what each code on those forms means, see our guide to Form 4 transaction codes, and for the broader definition of what counts as insider trading in the first place, see insider trading, defined.

Rule 10b5-1 trading plans and the cooling-off period

Rule 10b5-1 is a separate provision that gives insiders an affirmative defense against 10b-5 liability: if a trade was set up in advance under a written plan, made in good faith before the person had material nonpublic information, the trade is not treated as fraud even if the information later changes.

The SEC adopted amendments to Rule 10b5-1(c) on December 14, 2022, adding cooling-off periods before the first trade under a new or modified plan:

The amendments also added a checkbox to Forms 4 and 5 showing whether a reported transaction was intended to satisfy Rule 10b5-1(c)'s conditions, along with the plan's adoption date. That checkbox applies to reports filed on or after April 1, 2023, and does not apply retroactively to plans adopted before the amendments took effect.

Finding 10b5-1 trades in Form 4 data

SecFeed's insider trading data carries that checkbox as a field on each transaction, so you can filter for it directly instead of reading the filing by hand:

curl "https://secfeedapi.com/v1/insider-trading?ticker=NVDA&code=S&startDate=2026-01-01" \
  -H "Authorization: Bearer YOUR_API_KEY"

{
  "total": 1,
  "transactions": [
    {
      "ticker": "NVDA",
      "code": "S",
      "shares": 50000,
      "price": 134.20,
      "value": 6710000,
      "aff10b5one": true,
      "date": "2026-01-14"
    }
  ]
}

aff10b5one is true when the filer checked the Rule 10b5-1(c) box on that line of the form. There is no server-side filter for it yet, so pull a ticker's or company's transactions over a date range and filter the aff10b5one field client side:

from secfeed import Client

sf = Client("YOUR_API_KEY")
rows = sf.insider_trades(ticker="NVDA", code="S", startDate="2026-01-01")
plan_trades = [t for t in rows["transactions"] if t.get("aff10b5one")]

Full parameters for the endpoint, including the footnote and owner fields that often name the plan's adoption date, are at the insider trading API reference. See the Insider Trading API product page for the rest of what the endpoint returns.

What Rule 10b-5 does not do

A few limits worth keeping in mind when reading about the rule: it does not require advance SEC approval of a 10b5-1 plan, it does not make every trade by an insider who later turns out to have had bad information automatically illegal (good-faith plans adopted without material nonpublic information are the entire point of the Rule 10b5-1 defense), and it does not replace the separate, specific insider reporting obligations under Section 16. Reading Rule 10b-5 as "the insider trading law" is close enough for everyday purposes, but it is really the general fraud rule that insider trading claims, among others, are brought under.

Frequently asked questions

Does Rule 10b-5 only apply to company insiders?

No. The rule's text covers "any person" committing fraud in connection with buying or selling a security. Insiders who trade on undisclosed material information are the most common target of 10b-5 insider trading claims, but the rule is not written to apply only to them.

What is the difference between Rule 10b-5 and Section 16?

Section 16 and its forms (3, 4, 5) are a disclosure schedule for officers, directors and 10% owners: file on time or become delinquent. Rule 10b-5 is a general anti-fraud rule with no filing requirement of its own; a transaction can be reported correctly on Form 4 and still raise a 10b-5 question if it was based on undisclosed material information.

How do I know if a trade was made under a Rule 10b5-1 plan?

Check the transaction's checkbox on Form 4 or Form 5, which SecFeed exposes as aff10b5one in the insider trading endpoint. This only applies to reports filed on or after April 1, 2023, so earlier filings will not have it set even if a plan was in place.

What is the cooling-off period for a Rule 10b5-1 plan?

For officers and directors, it is the later of 90 days after adopting the plan or 2 business days after the next quarterly or annual report discloses financial results. For other people covered by the rule, it is 30 days. The issuer itself faces no cooling-off requirement.

Can a trade still violate Rule 10b-5 if it followed a 10b5-1 plan?

Yes, if the plan itself was not adopted in good faith, for example if it was set up or modified while the person already had material nonpublic information. The Rule 10b5-1 defense protects plans that genuinely predate that knowledge, not any trade that happens to be labeled as plan-based.