What is a Rule 10b5-1 Plan? Definition, Formula, and Example
A Rule 10b5-1 plan is a pre-arranged trading program that lets corporate insiders buy or sell company stock on a fixed schedule without violating insider trading laws.
What is a Rule 10b5-1 Plan?
A Rule 10b5-1 plan is a written trading arrangement adopted by a corporate insider — an executive, director, or large shareholder — that schedules future purchases or sales of the company's stock in advance, at a time when the insider does not possess material non-public information (MNPI). Once adopted, trades execute automatically according to the plan's instructions regardless of what the insider later learns. The plan provides an affirmative defense against insider trading liability under SEC Rule 10b-5: the insider can argue the trade happened because of the pre-existing plan, not because of inside knowledge.
How a 10b5-1 Plan Is Structured
A valid plan must satisfy specific conditions, tightened by SEC amendments effective 2023:
- Adopted in good faith while the insider is not aware of MNPI.
- Cooling-off period: for directors and officers, trading cannot begin until the later of 90 days after adoption or two business days after the earnings release covering the quarter of adoption (max 120 days).
- Specified terms: the plan must fix the amount, price, and dates of trades — either explicitly or via a formula (e.g., "sell 10,000 shares on the first trading day of each month if price ≥ $X").
- No subsequent influence: the insider cannot alter, or exercise later influence over, how trades execute.
- Single-trade plan limits and certifications: directors and officers must certify compliance, and issuers must disclose plan adoptions, modifications, and terminations in quarterly filings.
Trades under these plans appear on Form 4 filings with a notation that the sale was made pursuant to a 10b5-1 plan.
Worked Example
The CEO of a semiconductor company holds 2 million shares. In March, with no pending announcements, she adopts a 10b5-1 plan: sell 25,000 shares on the 15th of each month for 12 months at market, provided the price is at least $80.
After the cooling-off period, sales begin in July. In October the stock runs to $140 ahead of a blowout earnings report the CEO already knows about — the plan sells anyway. In February the stock dips to $78; that month's sale is skipped because the price floor isn't met. Total executed: roughly 275,000 shares sold across the year, every trade pre-committed and disclosed on Form 4 within two business days. Investors tracking insider transactions can see each sale tagged as plan-based.
When Traders Use This Information
- Signal filtering: a 10b5-1 sale carries far less informational weight than a discretionary insider sale. Smart money discounts scheduled plan sales when reading insider activity.
- Supply forecasting: large plan sales create predictable, recurring sell pressure that desks can anticipate.
- Red-flag detection: plan *terminations* or modifications shortly before bad news are themselves a signal — and a focus of SEC enforcement.
Limitations and Common Misconceptions
A 10b5-1 plan is a defense, not immunity — the SEC can still charge insiders who adopted plans while holding MNPI or who gamed modifications. Plan sales are not automatically meaningless: executives choose plan size and timing strategically, and clustering of plan adoptions after run-ups is itself informative. Also, the Form 4 checkbox only indicates a plan existed; it doesn't reveal the plan's terms, so outsiders can't always tell whether a sale was fully automatic or discretionary within plan bounds.