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Insider transactions
Almost every guide to Form 4 stops at what the codes mean. Almost none of them ask when the purchase happened relative to what the insider had just learned, which is the question that actually separates a signal from a scheduled trade.
10 min read· Corva Research
The short version
An executive spending personal money on his own company's stock is supposed to be the cleanest signal available to an outside investor. It is also, most of the time, close to meaningless.
The gap between those two sentences is timing. Two purchases can carry the same transaction code, the same dollar size, and the same job title, and still mean entirely different things, because one was decided the morning it was executed and the other was decided ninety days earlier by a formula. Form 4 does not label which is which. You have to read three facts together to tell them apart: three questions, asked in order, on one real filing, not a table of the twenty transaction codes. Plenty of pages already do that, and reading one will not tell you whether the purchase in front of you was informative.
Every officer, director and holder of more than 10% of a company's stock must report a change in beneficial ownership on Form 4, within two business days of the transaction. Each line carries a one-letter transaction code: P for an open-market or private purchase, S for a sale, and eighteen further codes for grants, exercises, gifts and transfers that never touched the open market. Code P is the only line where an insider chose, unprompted, to spend after-tax money on a stock they can already receive for free through compensation.
What most coverage of that code skips is the calendar the purchase sits inside. Public companies almost universally run a quarterly trading window under their own insider trading policy: it closes some weeks before the quarter ends and reopens only after earnings are released. That is company policy, not federal statute; no SEC rule mandates a blackout period, but the practice is close to universal. NASPP's June 2026 review of real trading window provisions found 40% of companies reopen exactly two trading days after earnings, and over three-quarters close it at least eleven days before quarter end.
A purchase in the first days after that window reopens is made by someone who has just finished a quarter nobody outside the company has fully absorbed. A purchase six weeks into the next quarter, in the quiet middle of the window, was made by someone with no more information than a careful reader of the last transcript. Same code. Same form. Different information content entirely.
Pull two dates before anything else: the transaction date on Form 4, and the date of the company's most recent earnings release or periodic report. Subtract one from the other.
None of this needs a subscription. The transaction date is a required field on every Form 4. The last earnings date is one search away, on the company's investor relations page or its 8-K filings under Item 2.02. The comparison takes under a minute.
Rule 10b5-1 gives an insider a defence against insider trading liability if a trade was made under a written plan adopted before the insider knew anything market-moving, then executed mechanically regardless of what happens later. The trade might land in the highest-information week of the quarter, but it carries none of that information, because the person who decided to buy is not the person buying today. Those can be two moments a year apart.
The SEC tightened this in December 2022. Under the amended Rule 10b5-1, effective 27 February 2023, a director or officer cannot trade under a new or modified plan until the later of 90 days after adoption or two business days after the issuer's next 10-Q or 10-K covering the quarter of adoption, capped at 120 days regardless. Everyone else gets a flat 30-day cooling-off period, to force real distance between decision and trade.
The rule also changed the form. For reports filed on or after 1 April 2023, Form 4 carries a checkbox for Rule 10b5-1(c) that a filer ticks when a transaction was made to satisfy that affirmative defence, plus a footnote stating the plan's adoption date.
Here is what that looks like on a real filing. Apple's SVP and General Counsel, Jennifer Newstead, reported a sale of 1,439 shares on 1 September 2026 on a Form 4 filed two days later. The 10b5-1(c) box is checked, and the footnote states the plan was adopted on 5 May 2026, four months before the trade. Whatever she knew on 1 September, she committed to that trade in May. That is the checkbox doing its job.
An unchecked box does not automatically mean a purchase is informative. It only means the affirmative defence is not being claimed for that line. Combine it with question one before drawing any conclusion.
A dollar figure on its own tells you almost nothing. The number that matters is the purchase set against two things the filer already has: existing ownership, and cash compensation.
Absolute dollars are the number every headline leads with, and it is close to the least useful of the four.
On 5 August 2026, biote Corp filed an 8-K under Item 2.02 reporting its quarterly results. Two days later it filed its 10-Q. On 10 and 11 August, its Executive Chairman and director, Marc D. Beer, bought stock on the open market: 115,950 shares at a weighted average of $1.53, then 16,000 more at $1.55. The Form 4, filed 12 August, shows exactly where each of the three facts sits.
| Field | What it shows |
|---|---|
| Reporting person, Item 6 | Marc D. Beer, Executive Chairman and director, not a 10% owner |
| Transaction date, Table I | 10 August 2026 and 11 August 2026, three and four trading days after the 8-K, one and two after the 10-Q |
| Transaction code, Table I | P, open-market purchase, both lines |
| 10b5-1(c) checkbox | Unchecked on both lines |
| Shares owned after transaction | 239,744, up from 107,794 before the first purchase |
Source: biote Corp Form 4, filed 12 August 2026, reporting owner Marc D. Beer, transactions dated 10 and 11 August 2026. Earnings release and 10-Q dates from biote Corp's 8-K and 10-Q filings, both filed the week of 3 August 2026.
Run the three questions. First, the calendar: the purchases land inside the first week after both the earnings release and the 10-Q, the highest-information stretch available under a working blackout policy. Second, the checkbox: unchecked, so no plan stands between the decision and the trade. Third, the size: the purchases more than doubled his direct holding, from 107,794 shares to 239,744.
Every one of those facts sits in a public filing, dated and checkable by anyone. None of them says whether biote's stock was a good buy at $1.53. That is not what the three questions answer, and this example is used only to show where the fields live, not to suggest an outcome.
Here is the honest counterweight. Insiders are frequently wrong, and the folklore around insider buying overstates it as a signal by a wide margin.
Executives buy their own stock for reasons that have nothing to do with superior information. Many companies require officers and directors to hold a minimum multiple of salary in stock, and a purchase that merely satisfies that guideline is closer to compliance than conviction. A newly appointed executive often buys in the first weeks of the job as a public signal of commitment, timed for optics rather than for any read on the quarter. And the same optimism that persuaded someone to take the job is the optimism that persuades them their stock is undervalued. The purchase can simply be restating who the person already is, not revealing anything new they learned.
None of the three questions here can tell genuine conviction apart from an ownership-guideline purchase or a signalling buy. A well-timed, size-appropriate purchase is still consistent with an insider who is simply, honestly, wrong.
Stated plainly, because a method that only lists its strengths is not one to trust.
A transaction code tells you what happened. It does not tell you when the decision was made relative to when the trader last saw the quarter, or what the purchase is against the stake already held. Those three facts, the calendar position, the checkbox and the size, turn a line on a form into a judgement, and all three sit in fields most readers skip past on the way to the transaction code.
Corva pulls a company's Form 4 filings alongside its own reporting calendar, flags whether a purchase falls inside the highest-information window, and shows the 10b5-1 status without you opening the raw XML. It does not tell you to buy anything. Figures are computed from the filed statements and cross-checked against SEC EDGAR. Where something cannot be determined, it says so rather than inventing an answer.
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Yes, for code P purchases by officers, directors and 10% owners. Section 16 requires the filing within two business days of the transaction.
No. It only means the filer is not claiming the Rule 10b5-1(c) affirmative defence for that line. The purchase could still be a routine top-up or a signalling buy. Questions one and three still have to be checked.
It is generally treated as stronger, since several people reaching the same decision independently is harder to explain away as one person's optics. This post has not verified a specific figure for how much stronger, and that comparison belongs in its own check.
No, and it would not if it could. Corva shows you the filing calendar and the disclosure fields. What you do with that reading is your decision, not a recommendation this post or the product makes.
Corva is a research tool, not a broker or investment adviser, and nothing here is a recommendation to buy, sell or hold any security. biote Corp and Apple Inc. are used here only to show where specific fields appear on a real Form 4 filing, not as commentary on either company's prospects. biote Corp figures are taken from its Form 4 filed 12 August 2026 (reporting owner Marc D. Beer) and its Forms 8-K and 10-Q filed 5 and 7 August 2026. The Apple Inc. example is taken from a Form 4 filed 3 September 2026 (reporting owner Jennifer Newstead). Cooling-off period and disclosure details are taken from the SEC's 14 December 2022 press release on amended Rule 10b5-1. Verify anything you intend to act on against the primary filing. See terms and disclaimer.