Transaction Codes Explained

Form 4 uses one and two letter transaction codes to describe what happened. Here is the plain-English glossary for every code you will see in the Blue Collar Picks feed, with a does-this-matter verdict for each.

The SEC defines a list of one and two letter transaction codes that appear on Form 4. Most readers only need to recognize five or six of them. The rest are context for tax events, plan administration, conversions, and gifts. This page covers every code you are likely to see in the Blue Collar Picks feed, with a plain-English verdict on whether it usually matters.

At a glance

CodeMeaningDoes this matter?
POpen-market purchaseYes. Strongest routine signal.
SOpen-market saleSometimes. Read in context.
AGrant or awardNo. Compensation.
FShares withheld for taxesNo. Mechanical.
DDisposition to issuerUsually no. Often a buyback.
MExercise of optionsRarely on its own. Watch what happens next.
XExercise of in-the-money derivativeSame as M.
GGiftUsually no. Estate or charity.
JOther (footnote required)Always read the footnote.
CConversion of derivativeRarely a fresh signal.
KEquity swapRarely. Usually advanced hedging or financing.
VVoluntary early reportingSignals deliberate transparency, not direction.

The full SEC list is in the Section 16 forms reference (PDF). The codes below are written for retail investors, not lawyers.

The five codes that matter most

P, open-market purchase

The insider used cash to buy shares on the public market. This is the signal most retail readers care about. It means the insider chose, with their own money, to increase their position. P is the strongest of the routine codes.

Common false read: assuming every P is bullish. A small token buy by a single director still does not move the needle. Look at size relative to the insider’s role, prior holdings, and whether other insiders bought in the same window.

S, open-market sale

The insider sold shares on the public market. Sales are noisier than buys. People sell for taxes, diversification, scheduled plans, home purchases, and other reasons that have nothing to do with the company. A single sale is rarely a story. A pattern of sales by senior insiders can be.

Common false read: treating any insider sale as bearish. Many sales are pre-scheduled under a 10b5-1 plan, which means the trade was queued months earlier and is not a fresh decision. Blue Collar Picks tags those rows with a Scheduled pill so you can spot the difference at a glance. See What is a 10b5-1 plan.

A, grant or award

Compensation. The insider received shares as part of a stock plan. It is not money out of pocket. Treat A as background, not signal.

Common false read: counting an A as insider buying. The data feeds on most tools include A in the insider activity stream and beginners mistake it for conviction. It is not.

F, shares withheld for taxes

When equity vests, insiders often surrender some shares to cover the tax bill. F is mechanical. It does not tell you anything about conviction.

Common false read: thinking F is a sell. The insider did not decide to lighten their position. The company withheld shares to settle a withholding tax. You will see F often because compensation vesting is regular.

D, disposition to the issuer

The insider returned shares to the company, usually as part of a buyback or a corporate action. Mechanical. Low signal.

Common false read: lumping D with S. The shares went back to the company, not to the open market. It does not reflect a personal view on the stock.

Options and conversions

M, exercise of options or conversion of derivative

The insider converted vested options into common stock. By itself, this is not a fresh purchase. What matters is what happens to the resulting shares. If the insider also sells them on the same day (often paired with an S row), it is more like compensation cash-out than insider buying.

Common false read: counting M as a buy. The cost basis was set when the options were granted years ago, not today.

X, exercise of in-the-money or at-the-money derivative

Similar to M. The insider exercised a derivative position. Read it the same way as M, with attention to whether the resulting shares are kept or sold.

The codes you will see occasionally

G, gift

The insider gave shares away, usually for estate planning or to a charitable trust. Total holdings decline, but it is not a market signal.

Common false read: treating a G as a sell. The insider’s view of the company has not necessarily changed.

J, other (footnote required)

J is the SEC’s catch-all. The filing must include a footnote describing what actually happened. Always open the source filing for a J transaction. The footnote will explain it in the insider’s own words.

Common false read: ignoring a J. The footnote is often where the most useful detail lives, especially around amendments, accounting cleanup, or unusual instruments.

C, conversion of derivative

A derivative position was converted into common stock. Like M, the economics were set earlier. Rarely a fresh signal on its own.

K, equity swap

Advanced hedging or financing. Most retail readers can treat K rows as noise unless paired with a clear footnote.

V, voluntary early reporting

The insider chose to file before the deadline. It says something about transparency, not direction. A V purchase is still a P-equivalent signal; a V sale is still an S-equivalent.

How Blue Collar Picks uses these codes

The default Purchases view filters to P only. The default Sales view filters to S only. The Cluster Buys and Big Buys views also filter to P. The Market Trades view shows open-market buys and sales with reported value. Use All Insider Transactions or All Form 4 Filings when you want grants, exercises, gifts, conversions, and other mechanical rows.

When you open a row in the drawer, the transaction type at the top is a link. It opens this page directly at the matching code so you can refresh the verdict without leaving the row.

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