What it means
The purpose of a lock-up period is always the same: to stop money leaving faster than the structure can cope with. In a newly listed company that means protecting the share price from a wave of insider selling, and in a fund it means sparing the manager from having to dump hard-to-sell assets to meet withdrawals.
After a listing, 180 days is the common length, counted from the first day of trading. Some agreements run 90 days, some run a full year, and many now release shares in tranches so the supply arrives gradually.
The exact dates are set out in the offering documents, so they are public information rather than a secret. Funds use lock-ups differently.
A hedge fund might impose a one year hard lock with no withdrawals at all, followed by quarterly redemption windows requiring 90 days notice. Private equity goes further still, tying capital up for eight to ten years because the underlying businesses cannot be sold quickly.
Investors should expect to be paid for accepting a lock-up, and that payment shows up as an illiquidity premium in the expected return. If two funds run the same strategy and one locks capital for three years, the locked one should be targeting a higher return to compensate.
The end of a lock-up is a scheduled, predictable event, which makes it unusual in markets. Analysts watch expiry dates on recently listed companies because the extra supply of shares often coincides with weaker prices and heavier volume.
In practice
Real-world examples
Example 1
An employee joins a start-up two years before it lists and receives shares that vest at listing. The 180 day lock-up means the paper wealth shown on the first day of trading cannot be turned into cash until the following winter, by which time the price has moved considerably.
Example 2
A family office commits $5,000,000 to a hedge fund with a two year lock-up and quarterly windows afterwards. When it needs cash in month fourteen for an unrelated purchase, it cannot access the fund and has to borrow against other assets instead.
Example 3
A pension trustee compares two infrastructure funds with almost identical strategies. One allows annual redemptions and targets 8%, the other locks capital for ten years and targets 12%, and the trustee treats the four point gap as the price of giving up access.
Think of it
Think of a lock-up period like a bungee jump instructor holding onto your safety harness until the initial bounce settles, making sure you do not scramble for the exit before the ride is stable for everyone.
Formula
Calculation
Lock-Up Expiry Date = Listing Date + Lock-Up Length
A company lists on 1 March with a 180 day lock-up. Counting forward 180 days gives 28 August as the final locked day, so insiders can first sell on 29 August.
The financial impact is easier to see in share terms. Insiders hold 5,000,000 locked shares and the stock trades at $20 just before expiry, so the paper value of the stock about to be released is 5,000,000 x $20 = $100,000,000.
If the extra supply pushes the price down to $17 in the week after expiry, that paper value falls to 5,000,000 x $17 = $85,000,000, a decline of $15,000,000, or 15%.
An insider who sold half the holding, 2,500,000 shares, on the first available day at $20 would have raised 2,500,000 x $20 = $50,000,000, while an insider who waited a week and sold the same quantity at $17 would have raised 2,500,000 x $17 = $42,500,000, a difference of $7,500,000.Case study
Seen in the real world
Verdanta Foods is an illustrative, invented company used to show how a lock-up period affects the people inside a business. It listed on 1 March at $22 a share with a 180 day lock-up covering 5,000,000 insider shares, including a substantial holding belonging to its operations director.
By late August the shares had drifted to $20 and the expiry on 29 August was widely known. In this fictional account, several insiders filed to sell in the first week, volume tripled, and the price settled at $17 before recovering to $19 over the following month. The operations director, who had assumed she should sell immediately, watched $2 a share evaporate on 1,000,000 shares, a paper cost of $2,000,000 against selling later.
Verdanta's board responded by arranging a structured selling plan for future insider disposals, spreading sales across several months rather than concentrating them in the days after expiry. The illustrative moral is that knowing the date is only half the job; deciding what to do on it is the other half.
Watch out
Common mistakes
- Assuming the lock-up ends on the anniversary of the pricing date. It usually runs from the first day of trading, and getting the start date wrong shifts the whole calculation.
- Treating a fund lock-up as the only barrier to getting money out. Notice periods, redemption windows and gates can delay access for months after the lock has technically expired.
- Selling everything the moment a lock-up lifts. That is precisely when supply is heaviest, and a staged sale over several months often realises a better average price.
Questions
People also ask
How long is a typical lock-up period after a listing?
Around 180 days is standard, with 90 day and 360 day variants and staged releases all in regular use.
Do share prices always fall at expiry?
Not always, but volume reliably rises and prices more often weaken than strengthen, so the date is worth planning around.
Can a lock-up period be shortened?
Yes, underwriters can waive part or all of it, and fund managers occasionally allow early redemption with a penalty fee.