IPO · LockupsWhen Insiders Can Sell
The dashed line is the IPO price. The amber mark is the day the main lockup ends (estimated from the prospectus date; companies can release shares early).
What usually happens around a lockup end
Return against the same stocks’ usual pace, trading days around the end of a 180-day lockup. 432 liquid US IPOs, 2018 to 2026. Hover the chart for each day.
Lockups in 30 seconds
Before an IPO, founders, staff and early investors agree not to sell for a set time, usually 180 days. When that lockup ends, a large block of shares can reach the market at once. This page lists every lockup ending soon, read straight from each company’s IPO prospectus, plus recent IPOs and the ones still in the pipeline.
Before the date
In 432 liquid IPOs from 2018 to 2026, the stock did 4.8% worse than its own usual pace over the 20 trading days before a 180-day lockup ended (t-stat −3.6, worse 59% of the time).
Right after
In the 5 trading days after, the same stocks did 1.9% better than usual (t-stat 2.2). The selling was mostly done in advance.
Big winners
Stocks up 50% or more since their IPO fell hardest: 12.6% worse than usual over the 30 trading days up to the lockup date, and 22% worse by 20 days after it (75 IPOs). Holders with big gains have the most reason to sell.
Small stocks
Across all 1,001 IPOs, including stocks under $5 or trading under $2M a day, there was no pattern (−0.7%, t-stat −0.65). That is why the list starts with liquid stocks only.
How the numbers were made, and their limits
- The sample
- Every final IPO prospectus (form 424B4) filed from 2018 to 2026, without blank-check companies (SPACs), matched to its first trading day. 1,001 had a price history covering the lockup date; 432 were liquid (price $5 or more and a median $2M or more traded a day in the month before).
- “Usual pace”
- Each stock’s return against the Russell 2000 (IWM) in the same window around day 180, minus its return against IWM in the same window around day 120 and day 240 after its IPO. New IPOs tend to lag the market all through their first year; this takes that out, so what is left is the lockup itself.
- Lockup length
- The study assumed 180 days, the most common length (about 7 in 10 prospectuses). The calendar uses the length each prospectus states.
- Dates
- A lockup runs from the prospectus date, the day the IPO is priced, usually the evening before trading starts. The end date shown is that date plus the lockup length, so it can be off by a day. Companies sometimes let insiders sell early (often after an earnings report), and some lockups end in stages.
- Pre-IPO shares
- Shares outstanding after the IPO minus the shares sold in it, as a share of all shares. Most are usually locked up, but not all: the prospectus lists the exceptions. For a company already listed abroad that is adding a US listing, most of these shares already trade at home.
- Limits
- Free price histories leave out companies that were delisted, which flatters every IPO’s numbers. The 2022 to 2026 part of the sample (104 liquid IPOs) points the same way but is too small to be statistically sure on its own.
- Sources
- SEC EDGAR full-text search and the prospectuses themselves (424B4, S-1, F-1). Prices from the site’s market data. The list refreshes every 6 hours.
Good to know. Prospectuses are read automatically, so an odd one can be misread; every row links to its filing. This is not a signal or advice to buy or sell.
For education only. Data comes from SEC filings and third-party price sources and may be delayed or wrong. Past patterns do not predict future results, and nothing here is investment advice or a recommendation to buy, sell or hold anything. See the Terms and Disclaimer.