IPO oversubscription and allotment in India

IPO oversubscription occurs when the total number of shares bid for by investors in an Initial Public Offering (IPO) exceeds the number of shares available for allotment in a given investor category. Oversubscription is the norm rather than the exception in well-received Indian IPOs; subscription multiples of 10× to 200× in the retail category are common, and very popular issues (such as Tata Technologies in 2023 or Bajaj Housing Finance in 2024) generate subscription multiples above 60× in the retail tranche alone. Allotment is the SEBI-prescribed process by which the registrar to the issue determines who receives shares when there is not enough supply to satisfy all bids. The allotment methodology depends on the investor category: retail applicants are allotted by computerised lottery when oversubscribed, non-institutional investors (NIIs) receive proportionate allotment, and qualified institutional buyers (QIBs) receive discretionary allotment within SEBI-set floors. The allotment process is documented in the basis of allotment published by the registrar on T+1.

Subscription multiples: reading the data

During the subscription window, the National Stock Exchange (NSE) and the Bombay Stock Exchange (BSE) publish rolling subscription data showing demand in each category as a multiple of the shares reserved for that category. The data is updated approximately every hour during trading hours on each day of the subscription period.

What the multiples mean:

• A retail subscription of 30× means that total retail bids received amounted to thirty times the shares reserved for the retail tranche.
• A QIB subscription of 10× means that total QIB bids received amounted to ten times the QIB allocation.
• The multiples are computed independently for each category; a 10× QIB does not imply anything about the retail or NII tranche.

Category independence: the allotment from each category’s reserved tranche proceeds independently. An investor in the retail category is not competing with QIBs or NIIs for the retail shares; the lottery or proportionate allotment operates entirely within each category.

Live data strategy warnings: many retail investors monitor the live subscription data to decide whether to bid, expecting to use high subscription as a signal of quality. This strategy has documented behavioural biases. QIBs routinely wait until the final hours of the last day of bidding to place their bids, so the first two days of QIB data may significantly understate final QIB interest. Retail and NII subscription, conversely, tends to be more evenly spread across days.

Retail allotment: the computerised lottery

When the lottery applies

For the retail category, SEBI mandates a computerised random lottery whenever the number of valid retail applications eligible for allotment exceeds the number of lots available in the retail tranche. An eligible application is one that:

1. Is at a bid price equal to or above the final issue price (or is a cut-off bid).
2. Has a valid UPI mandate acceptance (for UPI ASBA applicants) or a valid bank ASBA lien (for bank ASBA applicants).
3. Has passed the registrar’s third-party verification (PAN match with demat account, no duplicate application from the same PAN in the same issue in the same category).
4. Is for a valid lot-size multiple.

Applications that fail any of these checks are rejected before the lottery runs.

How the lottery works

The registrar assigns each eligible application a running serial number and then runs a randomisation algorithm to select the winning applications. The key feature of the retail lottery is that it operates on the count of applications, not on the value of shares bid:

• An application for 1 lot has the same probability of selection as an application for 13 lots.
• Applying for more lots than the minimum does not increase allotment probability when the issue is heavily oversubscribed.

This means that in a heavily oversubscribed issue, a retail investor’s optimal strategy is to apply for the minimum number of lots, the single minimum-lot application has the same probability of winning the lottery as a larger application, but the investor puts less capital at risk of being blocked for the subscription period.

Example: 60× retail oversubscription

Suppose an IPO has a retail tranche of 5,00,000 equity shares, and the lot size is 10 shares, giving 50,000 lots available for retail. If the issue receives 30,00,000 eligible retail applications (a 60× subscription), the lottery selects 50,000 of those applications at random. Each application has approximately a 1-in-60 chance (1.67%) of selection. A selected application receives one lot (10 shares at the issue price); all other eligible applications receive nothing.

Partial allotment in the retail category

SEBI’s prescribed retail allotment methodology does not allow for partial-lot allotment within the retail category when the issue is oversubscribed. Either an applicant receives one full lot (the minimum) or nothing. If the number of eligible applications is between the number of lots available and twice that number, the registrar may allot either one lot or zero lots in a way that distributes exactly the available lots; no applicant receives two lots in the first round until all eligible applicants have received one lot (a two-pass allocation). This methodology has been consistently applied by registrars since the SEBI circular of 2012 that standardised retail allotment.

NII allotment: proportionate within sub-categories

The December 2021 reform

Before December 2021, NII (non-institutional investor, also called HNI or high-net-worth individual) allotment was on a proportionate basis: an investor who applied for 10,000 shares in a 100× oversubscribed NII tranche would be allotted 100 shares (10,000 / 100). This system incentivised investors to apply for as many shares as possible to increase their proportionate allotment, creating extreme NII oversubscription multiples of 100×-500× in popular issues as investors borrowed funds to apply for large quantities.

SEBI circular SEBI/HO/CFD/DIL2/CIR/P/2021/2480/1/M dated 16 December 2021 split the NII bucket into two sub-categories:

• Small NII (sNII): investors bidding between ₹2,00,001 and ₹10,00,000. Receives one-third of the NII allocation. Allotment is proportionate within this sub-category, but the minimum allotment is one lot.
• Big NII (bNII): investors bidding above ₹10,00,000. Receives two-thirds of the NII allocation. Allotment is proportionate within this sub-category.

How proportionate allotment works

In a 50× oversubscribed sNII sub-category, an investor who applied for the minimum lot value (₹2,00,001 equivalent) would receive 1/50th of their bid quantity, potentially less than one lot. SEBI’s rules require a minimum of one lot to be allotted to each eligible NII applicant if there are enough lots to go around, with proportionate scaling above that minimum. If the oversubscription is so extreme that even a one-lot minimum cannot be guaranteed for all applicants, the allotment is a lottery within the NII sub-category (unusual in practice but technically possible in very heavily subscribed issues with many small NII applications).

In practice, NII proportionate allotment means that applying for a larger quantity increases the absolute number of shares received (but not proportionate probability), the opposite of the retail lottery dynamic.

QIB allotment: discretionary within SEBI floors

The QIB allotment process

For the QIB tranche (including anchor investors ), the allotment is discretionary: the book running lead manager and the issuer together decide which QIBs receive allotments and in what quantities, subject to:

• The total QIB allotment cannot exceed 50% of the net offer (75% for alternative-route issuers under SEBI ICDR Regulation 6(4)).
• Each anchor investor has already been allotted their shares at the anchor price on Anchor Day, receiving up to 60% of the QIB portion.
• Non-anchor QIBs receive the remaining 40% of the QIB allocation, allocated at the final issue price.
• Domestic mutual funds receive a minimum of 5% of the total QIB allocation, separate from the anchor tranche.

The discretionary nature of QIB allotment gives the BRLM significant flexibility in allocating to favoured institutional clients. SEBI does not currently prescribe a lottery or proportionate methodology for the QIB allocation; this is one of the most debated aspects of the Indian IPO framework, with critics arguing that it creates opportunities for the BRLM to reward relationship clients.

Undersubscription and spillover

If a category is undersubscribed (demand falls short of the reserved allocation), the unallocated portion is handled as follows:

• Retail undersubscription: the unallocated retail shares spill into the NII tranche if specified in the prospectus, or are added back to the QIB allocation.
• NII undersubscription: spills into the retail tranche or QIB, per the prospectus.
• QIB undersubscription (below 90% of overall issue): if the overall issue is subscribed below 90% of the total issue size, the issue fails and must be compulsorily withdrawn. All UPI mandates and bank ASBA blocks are released.
• QIB undersubscription above 90% of overall: technically possible if the QIB tranche is undersubscribed but retail and NII together push the overall past 90%. In this case the unsubscribed QIB portion is typically underwritten by the BRLM.

The failed issue

An issue is considered a failed issue if aggregate subscription across all categories (including the anchor allocation) is less than 90% of the total issue size (excluding anchor allocation). In a failed issue, SEBI regulations require the issuer to compulsorily withdraw the issue. All application amounts blocked under UPI ASBA or bank ASBA are released within one working day of the withdrawal announcement. Failed issues are rare; the most prominent recent example is the Adani Enterprises FPO of January 2023, which was withdrawn after full subscription due to extraordinary market circumstances, rather than undersubscription.

Post-allotment: the T+1 public announcement

The basis of allotment document is published on T+1 on:

• The registrar’s public portal (KFin at ipostatus.kfintech.com; Link Intime at linkintime.co.in).
• The BRLM’s designated website.
• The exchange website (NSE and BSE).

The document shows, for each investor category, the total number of applications received, the number of valid applications, the oversubscription multiple, the allotment ratio, and, for the retail lottery, the randomly selected serial numbers or equivalent identification of winning applications. Individual investors can check their allotment status on the registrar’s portal by entering PAN or application number.

The social dynamics of oversubscription: feedback loops

IPO oversubscription is self-reinforcing in ways that are worth understanding, because these dynamics affect both the final subscription multiple and the listing-day price.

The QIB late-bid effect

As described in the book building article, QIBs systematically wait until the final hours of the last day of the subscription window to place their orders, using the retail and NII subscription data accumulated over the first two days to calibrate their demand. A retail subscription multiple of 20× on Day 2 may attract QIB orders on Day 3 that push the QIB multiple from 2× to 15×, in turn attracting more NII interest in the final hours of the window. This three-category feedback loop is the mechanism by which very popular issues achieve extreme multiples of 60×-200× or more.

Media coverage and retail herding

Financial media and social media commentary on a live IPO subscription creates a herding dynamic: high early subscription generates news coverage that attracts more applications, which generates higher subscription that generates more coverage. SEBI’s real-time subscription data publication requirement, while designed for transparency, inadvertently enables this herding because investors treat high subscription multiples as a quality signal, regardless of whether the underlying business fundamentals support the valuation. Academic research has documented that retail participation in Indian IPOs is positively correlated with media coverage, and that media-driven retail participation contributes to higher listing-day returns that are partly reversed over the subsequent twelve months.

Grey-market correlation

The grey-market premium (GMP) tends to increase as subscription multiples increase during the window. An issue that shows 10× retail subscription on Day 1 may have a GMP of ₹50; if the same issue shows 60× retail subscription on Day 3, the GMP may have risen to ₹150. This correlation creates an additional feedback loop for investors who use the GMP as a quality signal: high subscription raises GMP, which attracts more subscription, which raises GMP further.

Allotment in fast-track and FPO issues

For follow-on public offers (FPOs) and fast-track issues, the allotment methodology is the same as for an IPO: retail lottery for oversubscribed retail tranches, proportionate for NII, and discretionary for QIBs. However, FPOs have an additional complexity: the company is already listed, and a secondary-market price exists alongside the FPO subscription price. If the FPO is priced at a discount to the secondary-market price (which is common as an incentive for retail participation), arbitrageurs may apply in the FPO retail tranche to capture the discount, which inflates the retail subscription multiple in a way that does not reflect genuine long-term investor demand.

The registrar’s role in fraud detection

Beyond allotment computation, the registrar performs a fraud-detection function: third-party verification that cross-checks the applicant’s PAN against the demat account linked to that PAN, the bank account linked to that PAN, and the SEBI database of known fraudulent entities. Applications where the PAN does not match the demat or bank account, or where the PAN is on a watchlist, are flagged and rejected before the allotment lottery runs. This verification catches:

• Benami applications (applications in fictitious names or with PAN mismatch).
• Applications from entities that have been debarred from capital-market participation by SEBI.
• Duplicate applications from the same PAN in the same category.

The registrar’s third-party verification framework was strengthened by SEBI circular SEBI/HO/OIAE/OW/P/2022/0001 dated 4 January 2022, which tightened the cross-linking requirements between PAN, demat, and UPI handle to reduce the scope for bogus applications.

References

1. Securities and Exchange Board of India (Issue of Capital and Disclosure Requirements) Regulations, 2018, Regulation 6 and Schedule VI, Allotment Methodology.
2. SEBI Circular SEBI/HO/CFD/DIL2/CIR/P/2021/2480/1/M dated 16 December 2021, Modifications to NII Allotment Methodology in Book Built Issues.
3. SEBI Circular SEBI/HO/CFD/TPD1/CIR/P/2023/140 dated 9 August 2023, T+3 Listing Timeline.
4. SEBI Circular CIR/CFD/DIL/3/2012, Standardisation of Retail Lottery Methodology.
5. KFin Technologies allotment-status portal: ipostatus.kfintech.com.
6. Link Intime allotment-status portal: linkintime.co.in.

See also

• Basis of allotment , the detailed SEBI methodology article
• Initial Public Offering , the broader IPO process
• Book building , the process generating the subscription data
• Retail individual investor , the category subject to lottery allotment
• Non-institutional investor , the category subject to proportionate allotment
• Qualified institutional buyer , the category subject to discretionary allotment
• Anchor investor , the QIB sub-category allotted before the public window opens
• IPO listing day , what happens on T+3 after allotment
• UPI ASBA , the retail application mechanism whose mandate is released on allotment
• Bank ASBA NetBanking , the alternative application mechanism
• KFin Technologies and Link Intime , the registrars managing allotment