Part 1: The Informational Intermediary Role of the Investment Bank

An Initial Public Offering ( IPO ) is the first sale of stock by a private company to the public . It becomes a public company. This transition depends critically on underwriters and investment banks. They value the company, set the offer price and allocate shares to investors. But one of the most robust empirical results in financial economics is that IPOs tend to be underpriced. IPO underpricing is the difference between the price at which the IPO is first offered and the price investors are willing to pay for the shares when they begin trading on the public market.

This is an important economic question, why would investment banks always underprice IPOs, why would they purposely sell shares at a price lower than their potential market value?

The answer is closely connected with the economic problem of information asymmetry. The term information asymmetry is used in modern economic analysis to describe a situation in which market participants do not have equal knowledge of the true value of an asset and was introduced by economists such as George Akerlof. For instance, in the IPO market, company insiders and investment banks usually know more about a company’s financial condition, growth prospects, and future profitability than outside investors.

Because there is no established market price for the new shares yet, investors are not sure if the shares are worth the price or overpriced. Thus, the investment bank plays an important information processing role of gathering private information from investors, estimating demand and translating uncertain expectations to a public offering price.

But this process also creates a fundamental pricing challenge. If the investment bank sets the price of the IPO too high, investors might not buy the stock and the offering will fail. This will harm the reputation of the company and the underwriter. If the investment bank prices the IPO slightly under its expected market value, demand will probably exceed supply, and the market debut will be a success.

Thus, underpricing is a way of coping with uncertainty rather than a simple valuation error.

Part 2: The Logic of Underpricing and the Winner's Curse

The economic rationale for IPO underpricing is based on the winner's curse, a theory developed by economist Kevin Rock. The theory suggests two groups of IPO investors, the informed and the uninformed investors who are not equipped with the private information about the quality of the offering .

Ininformed investors aggressively participate in IPOs that are underpriced and refrain from participating in IPOs that are overpriced. This is a problem for the unsophisticated investor who is more likely to get shares in low quality IPOs with weak demand. That is, uninformed investors face a selection problem: they get allocations when other investors do not want the shares.

This disadvantage has to be compensated by offering IPOs at a discount to the investors. The price must start low enough that even the uninformed expect a positive return, despite having no information.

Underpricing is therefore not an inefficient outcome, but a mechanism to overcome asymmetric information in the market. The discount is a payment for uncertainty, and serves to induce participation by investors who would not otherwise be willing to invest in newly issued securities.

This would give a similar logic as in the signaling theory. Signaling theory was developed by Michael Spence in the context of labour markets, to explain how people or firms use costly actions to signal hidden information. In the IPO market the investment bank’s pricing strategy is a signal about confidence and quality. A successful IPO, where the stock does well on the first day, indicates that investors are interested, and can enhance the company's reputation.

Part 3: Incentives at the Investment Bank, and the Cost of Leaving Money on the Table

Information asymmetry justifies the existence of underpricing, but it does not justify the conservative pricing preference of investment banks. It is about the incentive structure of underwriting.

Reputation is one of the most valuable assets for highly competitive investment banks. A successful IPO provides positive publicity, improved relations with institutional investors, and a better chance of winning underwriting contracts down the road. Thus, investment banks may care more about having an IPO that does well after it is listed, rather than having an IPO at the highest possible price.

A successful first day of trading gives the impression of a successful offering. There are investors who feel rewarded, analysts who provide positive coverage and an investment bank that earns credibility as an effective market intermediary. The reputational benefit may outweigh the value of the extra proceeds that could have been obtained by charging a higher initial price.

The economic cost of underpricing is often referred to as “money left on the table.” This is the difference between the capital raised at the IPO offer price and the higher amount of capital that could have been raised had the shares been sold closer to their first day market value.

Basically, if an investment bank prices shares at $20 and the stock immediately trades at $30, the company has given away $10 of potential value per share to new investors. This might look inefficient from the point of view of the issuing company, but the trade-off could be worth it for less uncertainty, more investor demand and a smoother transition into the public markets.

Part 4: Market Efficiency and the Problem of Price Discovery

The phenomenon of IPO underpricing also suggests that the concept of perfectly efficient markets is flawed. Efficient Market Hypothesis The prices of financial markets reflect all available information . The thing with IPOs is that they are a special case . The company's market price is not going to be known until it starts trading.

The investment bank has to value with no historical trading data. Unlike established public companies, where millions of transactions constantly update prices, valuation for IPOs is heavily dependent on forecasts, investor expectations and incomplete information.

The book-building process attempts to solve this problem by giving investment banks the opportunity to gather information from institutional investors before setting the offer price. Investors say they are willing to buy shares at a range of prices, which helps the underwriter gauge demand.

Yet, investors may not report perfectly accurate information due to strategic incentives. Investors may overstate or understate their true desire to influence pricing. Pricing errors are therefore inevitable to some extent.

Thus, underpricing can be interpreted as the market's equilibrium response to the problem of value discovery under uncertainty. And the discount isn’t a mistake. That’s the price you pay for converting private information into a publicly traded security.

Part 5: Is IPO Underpricing a Market Failure?

The question in the case of IPO underpricing is whether it is inefficient or necessary. From the perspective of the issuing companies, underpricing seems to be costly in the sense that it reduces the capital raised. But in a broader market setting, underpricing might actually improve efficiency by encouraging participation and reducing information problems.

If there is no underpricing, uninformed investors may stay away from the IPO market for fear that they will be at a disadvantage to more informed investors. This would reduce liquidity and make it harder for firms to access public capital markets.

Moreover, the firms often accept the underpricing, since the successful IPO brings benefits other than the immediate fund-raising. A good market debut can increase visibility, bring in future investors and enhance the firm’s ability to raise capital in future.

So, IPO underpricing is a trade-off between maximizing short-term proceeds and long-term market success.

Summary

Investment banks systematically under-price IPOs. This behaviour cannot be simply explained as a result of bad valuation or irrational decision-making. Instead IPO underpricing is the result of economics of information asymmetry, uncertainty and the difficulty of price discovery in a new market.

The investment bank acts as a middleman that helps solve information problems between firms and investors. The discount on IPO shares benefits investors against uncertainty, encourages participation and increases the chances of a successful offering. Their relationship with institutional investors and their standing in investment banks also benefits.

Finally, IPO underpricing is an illustration of how financial markets operate under incomplete information. Underpricing is not a mispricing but a strategic equilibrium between competing incentives of issuers, investors and investment intermediaries.

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R E F E R E N C E S

1. Akerlof, George. "The Market for Lemons: Quality Uncertainty and the Market Mechanism." Quarterly Journal of Economics, vol. 84, no. 3, 1970, pp. 488–500.
2. Rock, Kevin. "Why New Issues Are Underpriced." Journal of Financial Economics, vol. 15, no. 1–2, 1986, pp. 187–212.
3. Spence, Michael. "Job Market Signaling." Quarterly Journal of Economics, vol. 87, no. 3, 1973, pp. 355–374.
4. Ritter, Jay R. "The Long-Run Performance of Initial Public Offerings." Journal of Finance, vol. 46, no. 1, 1991, pp. 3–27.
5. Beatty, Randolph P., and Jay R. Ritter. "Investment Banking, Reputation, and the Underpricing of Initial Public Offerings." Journal of Financial Economics, vol. 15, no. 1–2, 1986, pp. 213–232.
6. Ljungqvist, Alexander. "IPO Underpricing." In Handbooks in Finance: Empirical Corporate Finance, edited by B. Espen Eckbo, Elsevier, 2007.