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Form 144

Notice of an intended sale of restricted or control securities, filed before the sale rather than after. It is one of the few genuinely forward-looking filings.

MadStockAlerts Research · Updated August 28, 2026

What to take away

  • It signals an intention to sell, filed ahead of the transaction.
  • The intended sale may be reduced or never executed at all.
  • Rule 144 also limits how much an affiliate may sell in a period.
  • The Form 4 filed afterward is what confirms whether the sale happened.
  • A cluster from several insiders is a different observation from a single notice.

MAD Academy Training Video · 0:45

A Notice of Intent to Sell

Form 144 signals a planned sale by an affiliate before it happens, which makes it the earliest warning of insider supply.

This lesson is part of a Stock Alerts + Tools plan.

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What it covers

Rule 144 governs the resale of restricted securities and of securities held by affiliates. Where the amount to be sold exceeds a threshold, a Form 144 notice is filed stating the security, the amount, the approximate date and the broker.

Restricted securities are shares acquired other than in a public offering: through a private placement, as compensation, or as consideration in an acquisition. Control securities are shares held by an affiliate regardless of how they were acquired.

Intent, not completion

This is the distinction that matters. A Form 144 says a sale is intended. The Form 4 filed afterward says what actually happened. Treating a 144 as a completed sale overstates it, and the two filings should always be read as a pair.

Notices are also frequently filed for the maximum permitted amount as a matter of routine, with a smaller quantity actually sold. Reading the headline number as the amount that will hit the market overstates the supply, sometimes considerably.

The volume limitation

Affiliates are limited in how much they may sell in any three-month period, calculated against shares outstanding or average weekly trading volume, whichever permits more.

This caps how quickly a large insider holding can be liquidated, which matters when assessing potential supply. A founder holding twenty percent of a company cannot exit it quickly through open-market sales even if they wish to, which is why large positions are more often sold through a registered secondary offering instead.

The cap is whichever of the two is larger
The cap is whichever of the two is larger05m10m15m20mWhichever bar is taller for thatcompany is the limit1% of shares outstandingAverage weekly volume, 4 weeksShares sellable in 90 days

Scroll the chart sideways to see all of it.

  • Liquid large-cap
  • Thin small-cap
For a liquid large-cap the volume test almost always binds; for a thin small-cap the share-count test does. The same rule produces very different practical limits. Illustrative.

Reading a run of them

A single 144 from one executive is routine. A cluster from several insiders within a short window is a different observation, and one that is visible only by looking at the company's filing index rather than at any individual filing.

The same caveats apply as to any insider sale: a cluster following a lock-up expiry or a vesting date is a calendar event rather than a view. The filing index shows the dates, and the proxy statement shows the vesting schedule.

Rule 144 and what it exists to solve

Securities that were not registered when issued cannot simply be sold into the market. Rule 144 provides a safe harbour: satisfy its conditions and the seller is deemed not to be an underwriter, which makes the sale permissible without registration.

ConditionRequirement
Holding periodSix months for a reporting company, a year otherwise
Current public informationThe issuer must be current in its filings
Volume limitationFor affiliates: the greater of 1 percent of shares outstanding or average weekly volume over four weeks
Manner of saleFor affiliates: ordinary brokers' transactions
NoticeForm 144 where the sale exceeds 5,000 shares or $50,000 in three months

The conditions apply differently to affiliates and non-affiliates. A non-affiliate who has held for long enough and where public information is current faces no volume limit and files nothing, which is why the disappearance of a large holder from the disclosure record does not mean they stopped selling.

This is also why Form 144 filings cluster after a lock-up expires. The restricted shares become eligible, the affiliates among the holders must give notice, and the notices arrive together without any of them representing a decision made that week.

Why a filing is not a sale

Form 144 is a notice of intent. It states that the filer proposes to sell up to a stated number of shares, and it carries no obligation to do so. The sale may be smaller, may happen later within the window, or may not happen at all.

What actually occurred is disclosed separately, on a Form 4, and only where the seller is subject to Section 16. A large holder who is neither an officer nor a director nor a ten percent owner files a 144 and no Form 4, so the intent is public and the execution is not.

This is the source of a recurring misreading. Headlines describing an executive selling a large amount are frequently written from a Form 144, which reports a maximum rather than a transaction, and the eventual Form 4 often shows a smaller figure.

The useful reading is the sequence rather than any single notice. A series of filings at regular intervals for similar amounts describes a programme, usually a 10b5-1 plan adopted in advance. An isolated notice for an unusually large amount, from someone who has not filed before, is a different observation.

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