Gabriel V. Rauterberg

The New Stock Market: Sense and Nonsense

How stocks are traded in the United States has been totally transformed. Gone are the dealers on NASDAQ and the specialists at the NYSE. Instead, a company’s stock can now be traded on up to sixty competing venues where a computer matches incoming orders. A majority of quotes are now posted by high-frequency traders (HFTs), making them the preponderant source of liquidity in the new market.Many practices associated with the new stock market are highly controversial, as illustrated by the public furor following the publication of Michael Lewis’s book Flash Boys. Critics say that HFTs use their speed in discovering changes in the market and in altering their orders to take advantage of other traders. Dark pools – off-exchange trading venues that promise to keep the orders sent to them secret and to restrict the parties allowed to trade – are accused of operating in ways that injure many traders. Brokers are said to mishandle customer orders in an effort to maximize the payments they receive in return for sending trading venues their customers’ orders, rather than delivering best execution. In this paper, we set out a simple, but powerful, conceptual framework for analyzing the new stock market. The framework is built upon three basic concepts: adverse selection, the principal-agent problem, and a multi-venue trading system. We illustrate the utility of this framework by analyzing the new market’s eight most controversial practices. The effects of each practice are evaluated in terms of the multiple social goals served by equity trading markets. We ultimately conclude that there is no emergency requiring immediate, poorly-considered action. Some reforms proposed by critics, however, are clearly desirable. Other proposed reforms involve a tradeoff between two or more valuable social goals. In these cases, whether a reform is desirable may be unclear, but a better understanding of the tradeoff involved enables a more informed choice and suggests where further empirical research would be useful. Finally, still other proposed reforms are based on misunderstandings of the market or of the social impacts of a practice and should be avoided.

Index Theory: The Law, Promise and Failure of Financial Indices

Financial indices, like the S&P 500 or the Consumer Price Index, have become a ubiquitous feature of our financial markets. One index, the London InterBank Offered Rate (“Libor”), may be the world’s most important number, an interest rate benchmark upon which hundreds of trillions of dollars depend. Yet, almost everyday new revelations emerge that Libor was tampered with during the height of the financial crisis by one or many of the world’s most prominent banks, with billions of dollars potentially misappropriated. This index disruption has attracted tremendous interest from regulators, private litigants, and market observers. Despite their importance, however, financial indices are poorly understood, and almost completely unstudied. In this Article, we explain why and how people use financial indices as well as how they are created. We show human discretion and value judgment to be essential ingredients in even the most “objective” indices. We then develop a taxonomy of financial indices, illustrating how the risks indices can pose, and the solutions applicable to those risks are intimately related to the motivation that drives the index’s creation. We show that the manipulation of indices is unsurprising given the precarious state of intellectual property rights in indices. While many call for prosecuting or regulating the Libor banks, our novel solution is to strengthen property rights for those who create financial indices.