What is Green Shoe Option in IPO and NCD Issue?

A Green Shoe option, formally known as an over-allotment option, is a provision in an underwriting agreement that allows the underwriters (investment banks) to sell more shares than originally planned in an Initial Public Offering (IPO).

From equity perspective, its primary purpose is price stabilization, ensuring the stock price doesn’t experience extreme volatility immediately after it begins trading on the secondary market.

How It Works

Typically, the agreement allows underwriters to sell up to 15% more shares than the original issue size. The process involves two main scenarios based on how the market reacts after the listing:

1. If Demand is High (Stock Price Rises)

If the IPO is a massive success and the price surges, the underwriters “exercise” the Green Shoe option.

1. Action: They buy the extra shares from the company at the original offering price and sell them to investors at that same price (fulfilling the “over-allotment” they made).
2. Result: This increases the supply of shares, which helps prevent the price from skyrocketing too fast and allows the company to raise additional capital.

2. If Demand is Low (Stock Price Falls)

If the stock price drops below the IPO offer price, the underwriters do not exercise the option.

1. Action: Instead of buying shares from the company, the underwriters buy shares back from the open market at the lower current price to cover their short position.
2. Result: This “buyback” creates artificial demand and reduces supply in the market, which provides a “floor” to the price and prevents it from crashing further.

Why Green Shoe?

The term comes from the Green Shoe Manufacturing Company (now known as Stride Rite), which was the first to use this mechanism in its 1919 IPO. It has since become a standard practice for most major public offerings to protect both the company’s reputation and the investors’ capital.

Yes, the Green Shoe Option (GSO) is fully valid and regulated in Indian equity IPOs. It was introduced by SEBI in 2003 and is currently governed under the SEBI (Issue of Capital and Disclosure Requirements) Regulations.

In the Indian context, it is formally known as the Price Stabilization Mechanism.

How it works in India

Unlike the NCD example we discussed earlier (where it is just about “keeping extra money”), the Equity GSO is a complex technical process involving a “Stabilizing Agent.”¹

The Mechanism: High vs. Low Demand

1. If the price falls below the IPO price (Price Support)

1. The SA uses the funds from the “over-allotment” (kept in an escrow account) to buy shares back from the secondary market.³
2. This buying activity provides a “floor” to the price, preventing it from crashing further.⁴
3. The shares bought from the market are then returned to the promoters to close the “borrowing” arrangement.⁵

2. If the price rises above the IPO price (Exercising the Option)

1. The SA does not buy from the market (as the price is already healthy).
2. Instead, the company allots new shares to the SA at the IPO price to replace the shares borrowed from the promoters.
3. The extra capital raised through these new shares stays with the company.

Common Use in India

While common in the US, the GSO is used less frequently in India compared to the “Retention of Oversubscription” in NCDs. However, large IPOs like Zomato (2021), Reliance Power (2008), and the LIC IPO (2022) (which had various stabilization clauses) are notable examples where these mechanisms or their variants were considered to manage post-listing volatility.

In the context of Non-Convertible Debentures (NCDs) in India, the “Green Shoe option” is technically referred to as the Retention of Over-subscription.¹

While the concept is similar to an equity IPO, the mechanics and purpose differ significantly in the debt market.

What it means for NCDs

When a company issues NCDs, it sets a Base Issue Size (e.g., ₹100 Crores). If the public demand is higher than this amount, the company can choose to keep the extra money instead of refunding it, provided they have a Green Shoe/Over-subscription clause in their offer document.²

Key Differences: Equity vs. NCDs

Regulatory Limits in India (SEBI)

As of 2025-2026, the rules under the SEBI (Issue and Listing of Non-Convertible Securities) Regulations are:

1. Standard Limit: Most corporate issuers are allowed to retain over-subscription up to 100% of the base issue size.(For example, if the base is Rs 500 Cr, they can collect up to Rs 1,000 Cr in total). Eg. Adani NCD opening on 6th Jan 2026, will have Green Shoe option
2. Special Categories: Following SEBI’s 2024 amendments, specific entities like Banks, NBFCs (Upper Layer), and All India Financial Institutions (e.g., NABARD, SIDBI) are permitted to retain over-subscription up to 5 times the base issue size to provide more flexibility in fund-raising.
3. Credit Rating: The credit rating obtained for the NCD must cover the entire amount, including the Green Shoe portion. If the rating is only for the base size, they cannot retain the extra funds.
4. Disclosure: The exact “Green Shoe” or “Retention” amount must be clearly mentioned in the Shelf Prospectus or Tranche Prospectus.

Why Companies Use It

1. Cost Efficiency: It is cheaper to retain extra money from one successful issue than to launch a fresh NCD issue later, which involves new filing fees and marketing costs.
2. High Demand: If the interest rate offered is attractive and the issue gets oversubscribed on Day 1, the company can immediately lock in more long-term funding.
3. No Dilution: Unlike equity, retaining more debt doesn’t dilute ownership; it only increases the company’s leverage.

What it means for you (The Investor)

If you apply for an NCD that has a large Green Shoe option, your chances of allotment are much higher. Even if the issue is “oversubscribed” by 2x, if the company has a 100% retention clause, every applicant may still receive a full allotment.