Algorithmic Trading and Market Regulation

This chapter examines the interaction between automated, algorithmic markets and fundamental legal concepts in securities regulation, an area to which policy-makers have devoted little attention. Recent advances in communication technology have facilitated the rapid rise of algorithmic trading and automated market mechanics. This chapter surveys eight framework notions critical to regulation and discusses how these might apply in an automated marketplace. Specifically, it examines reasonableness; strict liability; foreseeability; contribution; scienter; damage and harm; evidence and proof; and disclosure and information dissemination. This analysis reveals how deeply-held assumptions guiding regulatory law sit uneasily in today’s complicated and fast-paced markets.

Naked Open-Market Manipulation and Its Effects

More than 80 years after US federal law first addressed stock market manipulation, there is still dispute about manipulation law’s foundational principles; this chapter aims to provide clarity by offering an analytical framework for understanding a specific manipulation. There has been a sharp split among the federal circuits concerning manipulation law’s central question: Can trading activity alone ever be considered illegal manipulation? Economists and legal scholars do not agree on whether manipulation is possible in principle, let alone on how to address it properly in practice. The framework offered by this chapter aims to help clarify federal law and may guide regulators in successfully prosecuting financial law’s most intractable wrong. We draw on the tools of microstructure economics and the theory of the firm to provide an analysis of a particular form of manipulation, identify who is harmed by it, and evaluate the social welfare effects.

Better ‘Best Execution’

This chapter reviews best execution and new disclosure obligations in relation to investment advisers as well as brokers; it also provides an overview of the strategies they use to meet their rapidly changing obligations. Investment advisers and brokers are confronted with increasingly stringent regulatory and client expectations to fulfil their duty of best execution. Regulators in Europe have become active in developing formal best execution obligations, but the US Securities and Exchange Commission (SEC) is lagging behind in providing a clear framework for best execution. This chapter first outlines the analogous best execution obligation for broker-dealers and explores the contours of the SEC’s expectations for investment advisers. It then assesses the impact of new European best execution obligations and the role of public disclosures in aiding the fulfilment of best execution duties. It concludes by examining various strategies used by investment advisers to fulfil their evolving duties.

Is Trading Fast Dangerous?

This chapter discusses the findings of the growing theoretical and empirical literature on trading speed in financial markets. The speed of trading has increased significantly in recent years, due to progress in information technologies and automation of the trading process. This evolution raises many questions about the effects of trading speed. It is argued that an increase in trading speed raises adverse selection costs but increases competition among liquidity providers and the rate at which gains from trade are realized. Thus, the effect of an increase in trading speed on market quality and welfare is inherently ambiguous. This observation is important for assessing empirical findings regarding the effects of trading speed and policy-making.

High Frequency Trading and Circuit Breakers in the EU

This chapter reviews the fundamental workings of the EU regulatory framework and its implications for high frequency trading (HFT) and the latest findings on the market realities in the EU. Over the last decade, securities trading landscapes have undergone significant change, with the emergence of HFT being one of the most important developments in this context. At the same time, the EU has made landmark legislative advances with the aim of increasing investor protection, market order, and financial stability, and of containing risks in those areas. As the new MiFID2 legal framework takes effect, a wealth of new data and evidence will become available in coming years that will improve understanding of HFT patterns, the effectiveness of circuit breakers, and their optimal calibration.

Regulating High Frequency Trading and Dark Liquidity in Australia

This chapter focuses on how the Australian Securities and Investment Commission’s general regulatory approach has informed its response to the challenges facing investor trust and confidence as a result of high frequency trading and the growth in dark liquidity. Technological change, increasing competition, and globalization mean that financial markets are changing more rapidly than ever before, posing a number of challenges from a regulatory perspective. This is particularly true for exchange markets: innovation and advances in information technology are delivering lower costs for investors, yet alongside these positive developments is a need for continued testing, monitoring, and accountability. In this context, the chapter discusses ASIC’s responses to both real and perceived problems in the market, as well as the changes stimulated by ASIC’s actions.

What has Changed in Four Years?

This chapter revisits the findings of Battalio, Corwin, and Jennings (2016), who used public order routing data to examine the order routing of several large retail brokerages in 4Q2012. They found that brokerages generally employed one of two order routing strategies: they appeared either to route all customer orders in a given stock to a market maker (wholesaler), or to route marketable orders to wholesalers and nonmarketable orders to exchanges that offer relatively large liquidity rebates. Importantly, the researchers also provided empirical evidence suggesting that routing orders in a manner that maximizes order flow payments can result in diminished execution quality. This chapter examines the extent to which retail broker order routing decisions and patterns have changed since 2012. It finds that despite increased public and regulatory scrutiny, the practice of routing retail orders to maximize order flow payments remains pervasive.

The FX Race to Zero

This chapter traces how technological changes have affected the structure and operation of currency markets, and examines the issues associated with these developments. These changes have caused significant concern within the industry and raise complicated questions about whether additional regulation is necessary. Nevertheless, they have received relatively little theoretical or empirical attention in comparison to similar developments in equities markets. To address this gap, the chapter outlines the primary market structural issues in foreign exchange markets, including potentially abusive trading techniques, last look, and perverse incentives to monetize access to speed and information. Further, the chapter provides an example of a high frequency latency arbitrage opportunity and discusses the potential mitigating impact of a randomized delay mechanism. This is followed by an analysis of recent regulatory efforts to address these issues in the UK, the EU, and the US, in addition to a review of industry-led initiatives to establish best practices for algorithmic traders and venue operators. The chapter concludes by discussing key questions and constraints for future research.

A Comparison of Execution Quality across US Stock Exchanges

The fragmented nature of the US equities exchange landscape has given rise to structural inefficiencies, creating the potential for conflicts of interest between market participants. The introduction of the Investors Exchange offers the opportunity to evaluate market quality across exchanges with varying fee structures. The chapter studies four dimensions of market quality—liquidity, execution costs, price discovery, and market stability—and examines structural mechanics responsible for disparities in execution quality. A trend is observed in venue stratification by fee structure: maker-taker exchanges dominate the US equities trading landscape despite greater adverse selection, less stability around executions, significantly longer queues at the inside, and a lower probability of execution in aggregate. This suggests that access fees and rebates perpetuate economic incentives misaligned with the tenets of best execution, and may promote activity detrimental to market quality. The chapter employs a publicly available dataset (Daily TAQ) to facilitate replication of our metrics.

A Case Study in Regulatory Arbitrage and Information Asymmetry

While much of the public debate surrounding high frequency trading (HFT) and algorithmic trading has centred on speed, less has been said about the circumvention of regulation via special order types—complex and often non-transparent ways for high frequency traders to interact with exchange markets and other trading venues, allowing them to achieve a favourable execution position at the expense of other market participants. This chapter documents the special order types used by high frequency traders, the absence of adequate disclosure by exchanges, and the problematic interaction between order types designed to accommodate HFT strategies and the order types typically employed by public investors and agency brokers.