By ipomarket.in Editorial Team · Last reviewed: 2026-09-10
Disclaimer: This article is for informational purposes only and does not constitute investment advice. IPO investments are subject to market risks. Please read the offer document carefully and consult a SEBI-registered investment advisor before investing.
When a company lists on the stock exchange, not everyone can sell their shares on day one. Promoters, early backers and large institutional buyers are held to a set of holding restrictions called lock-in periods. These are mandated by SEBI and are one of the more misunderstood parts of the IPO process. This guide walks through who is locked in, for how long, and why it matters when you assess a newly listed stock.
What is a lock-in period?
A lock-in period is a window during which certain shareholders cannot sell or transfer their shares after an IPO. It applies to specific categories of holders, not to everyone. The rules are set out mainly under Regulations 16 and 17 of the SEBI ICDR (Issue of Capital and Disclosure Requirements) Regulations, 2018. Regulation 16 covers the minimum promoter contribution, while Regulation 17 covers pre-issue capital held by non-promoters. For SME IPOs, a separate set of provisions (Regulation 238 onwards) applies with generally stricter terms.
The purpose is straightforward. Lock-ins keep newly listed shares from being flooded onto the market immediately after listing, which helps price stability. They also signal that promoters and early investors remain committed to the business beyond the listing event, rather than treating the IPO purely as an exit.
Promoter lock-in: 18 months and 6 months
Promoter shares are split into two buckets for lock-in purposes.
- Minimum promoter contribution (the core holding): This portion is locked in for 18 months from the date of listing. It represents the minimum stake promoters must contribute and hold to demonstrate skin in the game.
- Excess promoter shareholding: Any promoter shares beyond the minimum contribution are locked in for 6 months from listing.
These durations were shortened materially by the SEBI ICDR (Second Amendment) Regulations, 2021, notified on 13 August 2021. Before that amendment, the minimum promoter contribution was locked in for three years and the excess for one year. SEBI cut these to 18 months and 6 months respectively, reflecting a more mature market where extended lock-ins were seen as less necessary.
One nuance worth knowing: promoters can pledge locked-in shares as collateral, subject to conditions. Such pledges must be with approved lenders such as scheduled commercial banks, public financial institutions, systemically important NBFCs or housing finance companies. Pledging is regulated but not prohibited during the lock-in.
Pre-IPO investors (non-promoters)
Venture capital funds, private equity investors, strategic backers and other non-promoter shareholders who held shares before the IPO fall under Regulation 17.
- Standard rule: The entire pre-issue capital held by non-promoters is locked in for 6 months from the date of allotment.
- High-stake exception: For companies listing without a demonstrated profitable track record (those coming under Regulation 6(2)), shareholders holding more than 20% of the pre-IPO shareholding face a 1-year lock-in from the allotment date, per the research reviewed.
There is also a holding-period exemption for Category I and Category II Alternative Investment Funds (AIFs), Venture Capital Funds and Foreign Venture Capital Investors. Broadly, if these funds held their shares for a specified minimum period before the offer document was filed, they may qualify for relief from the standard lock-in. The precise conditions vary and should be checked against Regulation 17 and the specific company's red herring prospectus.
Employee ESOPs: insiders versus former holders
Employee stock options are treated differently depending on who holds them.
- Current employees: According to the sources reviewed, current employees who exercised ESOPs before or around the IPO are not subject to a mandatory lock-in on those shares and can sell in line with retail allottees. This point rests on secondary sources rather than direct SEBI text, so treat it as indicative.
- Pre-IPO ESOP shares held by ex-employees or others: Shares allotted before the IPO under an ESOP or ESPS scheme are generally locked in for 6 months, unless exempted or otherwise disclosed in the RHP. In practice, ex-employees' pre-existing shares are treated like other pre-IPO capital.
Anchor investors: a phased 30-90 day unlock
Anchor investors are large institutional buyers who commit to the issue a day before the IPO opens. Their allotment unlocks in two stages under current guidelines:
- 50% of anchor shares are locked in for 30 days from the date of allotment.
- The remaining 50% can only be sold after 90 days.
This staggered structure was designed to prevent a single large sell-off by anchors soon after listing. You can read more about how these categories interact in our guide to IPO investor categories: QIB, NII and retail.
Retail investors: no lock-in
If you applied for and received shares through the public issue as a retail investor, there is no mandatory lock-in. You are free to sell on listing day or hold as long as you wish. This is the key difference between retail allottees and the categories above. How you time that decision is a separate question, covered in our listing day strategy guide.
SME IPOs: longer promoter lock-ins
SME IPOs follow stricter rules. Per the sources reviewed, the promoter's minimum contribution in an SME IPO is locked in for at least three years from the date of allotment, considerably longer than the 18 months on the mainboard. This reflects the higher risk profile of smaller, less-seasoned companies and SEBI's intent to keep promoters invested for longer. The distinction is one more reason SME and mainboard listings are not directly comparable.
Recent and proposed changes
SEBI has been fine-tuning rather than overhauling the framework.
In November 2025, SEBI released a consultation paper addressing a technical gap: pre-IPO shares pledged as collateral could not be formally "locked in" because of depository system limitations. The proposal, as reported, is to mark such pledged shares as "non-transferable" rather than "locked-in", which would satisfy the regulatory objective without disrupting the investor's financing arrangement. The implementation timeline for this proposal was not disclosed in the sources reviewed.
Separately, sources point to 2024-2025 amendments clarifying rules around pledged shares during lock-in and, in one reading, requiring non-promoter shareholders with over 20% stake to retain a portion of their shares for a year. The exact wording should be verified against the current ICDR text before relying on it.
What happens at lock-in expiry?
Lock-in expiry dates are predictable, disclosed events. Each company's RHP sets out the lock-in terms, and the exchanges publish expiry information. When a large tranche unlocks, a portion of previously restricted shares becomes tradeable, which can create short-term selling pressure and volatility.
However, the effect is not automatic. The research reviewed suggests that lock-in expiries have often produced limited observable impact on share prices, since much depends on whether locked-in holders actually choose to sell and on broader sentiment. To put the scale in perspective, one source estimates that between December 2025 and March 2026 roughly 108 companies were scheduled for lock-in expiries, with shares worth around ₹3 lakh crore unlocking over that window. These figures are reported estimates tied to that specific period and should not be read as a permanent state.
For a retail investor, the practical takeaway is that a lock-in expiry is worth noting during post-listing due diligence but rarely justifies panic. Tracking expiry dates via the RHP and exchange disclosures is simply part of understanding a stock's supply dynamics.
FAQ
How long is the promoter lock-in in an Indian IPO?
Under SEBI ICDR Regulations, the minimum promoter contribution is locked in for 18 months from the date of listing, and any promoter shareholding above that minimum is locked in for 6 months. These durations were shortened from three years and one year respectively by the August 2021 amendment.
Do retail investors have a lock-in period?
No. Retail investors who receive shares through a public issue face no mandatory lock-in and can sell on listing day or hold for as long as they choose.
How does the anchor investor lock-in work?
Anchor allotments unlock in two stages: 50% after 30 days from allotment and the remaining 50% after 90 days. This staggering is meant to prevent a sudden large sell-off by anchors soon after listing.
Why are SME IPO lock-ins longer?
SME IPO promoter contribution is locked in for at least three years, compared with 18 months on the mainboard, per the sources reviewed. SEBI applies stricter terms to smaller, less-established companies to keep promoters invested longer.
Should I worry when a stock's lock-in expires?
Lock-in expiry can bring short-term volatility because more shares become tradeable, but studies cited suggest the price impact is often limited. It is a disclosed, predictable event worth tracking, not a reason to sell automatically.
Last reviewed: 2026-09-10. Lock-in rules can change through SEBI amendments; always verify against the current ICDR Regulations and the specific company's offer document.