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Overallotment: Definition, Purpose, and Example


Overallotment is a situation where underwriters sell more shares than the agreed amount during an initial public offering (IPO), intending to stabilize the market price if demand is high. This strategy provides additional liquidity and aids in managing downward price pressure. An example would be if a company’s IPO is for 1 million shares, but due to high demand, underwriters sell 1.15 million shares, with the extra 150,000 shares representing the overallotment.


The phonetic spelling of “Overallotment” is: /ˌoʊvərəˈlɑtmənt/

Key Takeaways

<ol> <li><strong>Definition:</strong> Overallotment refers to the situation when underwriters sell more shares than are initially offered in an IPO (Initial Public Offering). It is also called a “Green Shoe Option,” which grants the underwriters the right to sell investors more shares than initially planned by the issuer in case of high demand.</li> <li><strong>Purpose:</strong> The main purpose of an overallotment is to stabilize the after-market price of a security after the IPO. It allows underwriters to prevent stock price depreciation by buying back the extra shares at the offering price, thus creating a buffer against post-IPO volatility. This also provides additional protection to investors against loss.</li> <li><strong>Example:</strong> For instance, Company A plans an IPO for 1,000,000 shares. The underwriters may utilise the overallotment option and sell 1,150,000 shares. If demand is high, they’ll sell the additional 150,000 shares at market price. If the price drops, they can choose to buy back the extra 150,000 shares at the lower price, thus helping to stabilize the share price.</li></ol>


Overallotment, also known as greenshoe option, is a vital financial term in the realm of initial public offerings (IPO). It provides underwriters the authority to sell investors up to an additional 15% shares more than the original amount specified by the company going public. The purpose of this provision is to stabilize the stock price if demand exceeds expectations. It mitigates the risk of acute share price fluctuations that can dissuade potential investors. An example of this would be if Company A decides to go public and launch an IPO of 1 million shares. By adopting an overallotment option, their underwriters have the ability to sell an extra 150,000 shares (15% of 1 million). Therefore, they can prevent undue market disruption if the demand for Company A’s shares is substantially higher than anticipated. This mechanism significantly contributes to maintaining a balanced and reliable financial market.


There are multiple reasons why an issuer may choose to use an overallotment strategy in finance. The primary purpose of an overallotment is to stabilize the price of a security after it’s been issued to prevent any sharp downfall in its price. By presenting additional shares for sale, the firm ensures that there’s a surplus supply of the security in the market, reducing the chance of a shortage that might drive up the prices exponentially. This action safeguards the market from excessive volatility which might scare off potential investors and destabilizes the IPO process. Furthermore, it provides an added safety net to cover any unexpected demand from the public.For illustration, let’s take the example of a company that plans to issue 1,000 shares in its initial public offering (IPO). If it anticipates a particularly strong demand for these shares, it might incorporate an overallotment provision into its underwriting agreement, allowing for the sale of up to 1,150 shares. If demand doesn’t wind up being as strong as anticipated, the company just sells the initial 1,000 shares. However, in case the demand is indeed high, the company has the flexibility to distribute those extra 150 shares, hereby cushioning the effect of the surge in demand, and helping maintain the stock’s price stability in the immediate aftermath of the IPO.


Overallotment is a situation in which more shares are sold than initially planned during an initial public offering (IPO). It arises when the underwriters of an IPO sell additional shares to the public if the demand exceeds expectations. This term is also known as Greenshoe option. Now, let’s move to the real-world examples:1. LinkedIn’s IPO: In 2011, when LinkedIn went public, it was priced at $45 per share initially. Due to the high demand, the underwriters went ahead with an overallotment. They sold more shares than they had initially planned. Because of the overallotment, they were able to stabilize the price, and the closing price of LinkedIn reached $94.25, which was more than double the initial asking price.2. Facebook’s IPO: During Facebook’s IPO in 2012, underwriter Morgan Stanley over-allotted shares to stabilize the price of Facebook Inc. (FB)’s after a disappointing debut. An extra 63 million shares were issued as a part of the overallotment option.3. Alphabet Inc. (Google’s) IPO: During Alphabet Inc. (known as Google at that time)’s IPO in 2004, the overallotment option was utilized due to better-than-expected demand. The underwriters sold 25.9 million shares at the initial offering price of $85 per share, raising an extra $194 million, above and beyond the capital they had expected to raise.

Frequently Asked Questions(FAQ)

What is an overallotment?

An overallotment is a specific situation related to initial public offerings (IPOs) where more shares are sold than initially planned. This typically happens when demand is high and underwriters take advantage of the situation to sell additional shares.

What is the purpose of an overallotment?

The purpose of an overallotment is for the issuer to protect itself from falling prices and to stabilize the aftermarket price of the IPO. It also benefits underwriters who have the option to purchase more shares at a lower cost if the demand is high.

How does an overallotment work in finance?

In finance, an overallotment involves selling more shares than what was initially declared in the securities offering proposal. If the shares’ demand exceeds the initial supply, the underwriters will exercise the overallotment option and sell these surplus shares.

Can you provide an example of an overallotment?

Sure. Suppose a company plans an IPO to sell 1 million shares, but the demand is much higher. With an overallotment facility, the underwriters have the ability to sell an additional 200,000 shares (presuming a 20% overallotment). So, instead of 1 million, 1.2 million shares could potentially be sold.

How does overallotment benefit investors?

The overallotment option helps stabilize the share price in the immediate aftermath of an IPO by providing additional supply and preventing the share price from going up too quickly. It can also possibly prevent a sudden drop in share prices.

Who decides on an overallotment?

The decision to utilize the overallotment option is typically made by the underwriters of the IPO. If they think demand will exceed supply, they may decide to implement the overallotment feature.

Is overallotment a common practice in the finance industry?

Yes, overallotment is a fairly standard practice in securities offerings, particularly in IPOs. It is usually included in the underwriting agreement between the issuer and the underwriters.

Related Finance Terms

  • Over-Subscription: This term refers to a situation where the demand for an initial public offering (IPO) of securities exceeds the number of shares issued. This is a common scenario when an overallotment occurs.
  • Green Shoe Option: The Green Shoe Option is a clause contained in the underwriting agreement of an IPO, which allows underwriters to buy up to an additional 15% of company shares at the offer price. This is closely related to overallotment as it gives underwriters the ability to meet excess demand.
  • Underwriters: Underwriters are professionals who evaluate and assume another party’s risk for a fee, like a commission, premium, spread, or interest. They play a critical role in the process of overallotment as they are authorized to sell more shares than initially planned.
  • Secondary Offering: This refers to the sale of new or closely held shares by a company that has already made an IPO. If overallotment leads to the issuance of new shares by the company, it becomes a secondary offering.
  • Short Selling: This investing method is used by underwriters in the overallotment process. Short selling is the sale of a security that is not owned by the seller or that the seller has borrowed, anticipating that the market price will fall.

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