IPO Lock-Up Periods Explainer
An IPO lock-up is a contract that restricts company insiders, employees, founders, and other large pre-IPO holders from selling or otherwise transferring covered securities for a stated period after the offering. The agreement is typically made with the underwriters rather than imposed as a general statutory holding period.
Lock-ups help prevent a large wave of insider supply from reaching a newly public market immediately. Terms vary in length, covered transactions, derivative hedges, exceptions, and whether the lead underwriter may grant an early waiver. The IPO prospectus describes the material restrictions.
Expiration does not mean every holder will sell, but it can increase the number of shares eligible for sale and affect expectations or price. Other limits may still apply, including securities-law resale rules, blackout policies, possession of material nonpublic information, and contractual vesting.
Investors should identify the exact expiration calculation, number of locked shares, staggered releases, waiver provisions, earnings dates, and float. A lock-up supports an orderly transition; it does not prove insider confidence or set the value of the business.
Insiders and pre-IPO holders agree not to transfer covered securities temporarily.
The prospectus explains the actual terms.
More shares may become eligible for sale when restrictions end.
Eligibility does not mean every holder will sell.
Vesting, blackout rules, insider-trading law, and resale rules may still apply.
Analyze the full share-release schedule.
Explore more "Explainers"
Discover additional explainers across politics, science, business, technology, and other fields. Each explainer breaks down a complex idea into clear, everyday language—helping you better understand how major concepts, systems, and debates shape the world around us.