Stock Exchange Merger and Liquidity: Evidence from the Euronext Merger Ulf Nielsson† First draft: April 2007. This version: February 2008 Abstract The paper empirically investigates the effects of the Euronext stock exchange merger on listed firms, i. the merger of stock exchanges in Amsterdam, Brussels, Lisbon and Paris. Specifically, it examines how exchange consolidation has affected stock liquidity and how the effect varies with firm type, i.
what types of firms benefit the most in terms of stock liquidity. The results show asymmetric liquidity gains from the stock exchange merger, where the positive effects are concentrated among big firms and firms with foreign sales. There is not a significant increase in stock liquidity of small or medium sized firms, or firms that only operate domestically. Beyond the significant size and foreign exposure effects (i.
big firms and firms with foreign sales gain), the analysis finds no systematic pattern in the distribution of merger benefits across industries or listing locations. The results are robust to different model specifications and the key conclusions are consistent across various dimensions of liquidity (i. amount of trading, cost of trading and market depth). Competitive effects of the merger are also analyzed, i.
the merger effect on relative market shares (share of trading) of European exchanges. The merger is associated with an increase in Euronext’s market share, where the increase is drawn from the London Stock Exchange. There is however no evidence of Euronext enhancing its competitive stand in terms of attracting new firm listings. Keywords: Liquidity, stock exchange, integration, merger.
candidate Columbia University and affiliated faculty at Reykjavik University (uvn1@columbia. Currently under 2nd revise & resubmit at the Journal of Financial Markets. An earlier version of this paper received the Joseph de la Vega prize 2007, awarded by the Federation of European Securities Exchanges. Many thanks to Ailsa Röell for numerous discussions and invaluable guidance.
I am also grateful to Lawrence Glosten, Eric Verhoogen, Catherine Thomas, Charles Jones, Albert Menkveld, Richard T. Meier and Pierre-André Chiappori for valuable comments and conversations. I also greatly benefitted from useful comments from participants at seminars at Columbia University, University of Iceland and the European Commission. Also thanks to Kathleen M.
Dreyer, Rafael Plata and Euronext Statistics for data assistance and to Columbia University for financial support from the Wueller and Vickrey research funds. All remaining errors are my own. 1 Introduction The business environment of stock exchanges has changed considerably in the last decade. The typical government/member owned, national stock exchanges have largely been replaced by for-profit, publicly listed exchanges.1 These transformed stock exchanges increasingly operate at an international level, offering world-wide menus rather than merely serving a national appetite.
The transition has been accompanied by an immense increase in international stock exchange integration and co-operation. For example, stock exchanges have established strong operational ties with the usage of joint trading systems and the harmonization of regulations. Interestingly, this increased level of integration has recently taken a new turn as stock exchanges have sought partners to create fully merged identities. The most noteworthy merger activities include the Euronext merger, the OMX merger, the NYSE-Euronext merger and ongoing consolidation between NASDAQ and OMX on the one hand, and the London Stock Exchange and Borsa Italiana on the other.2 The impacts of such stock exchange mergers are largely unknown.
There are many aspects of interest in such an analysis, both economic and regulatory issues which affect investors, firms, financial intermediaries and the overall economy. Thus, any profound study of the effects of stock exchange merger is bound to be selective and incomplete in its coverage. This paper narrows the focus by examining how consolidation of exchanges has affected the market liquidity of traded stocks. In particular, have all firms gained from merger in terms of stock liquidity? Or are the gains perhaps asymmetrically distributed? If so, which types of firms have benefited the most from stock exchange merger? Does it depend on firm size, industry, location or any other characteristics? These are the key questions that the paper sets out to answer.
This is done by empirically investigating the effects of the Euronext stock exchange merger on listed firms, i. the merger of the stock exchanges of Amsterdam, Brussels, Lisbon and Paris. Also, in addition to such a firm heterogeneity analysis, the paper also attempts to measure the competitive effects on 1 In 1998, 38% of exchanges in the World Federation of Stock Exchanges were for-profit. In 2004 this figure was up to 69% (World Federation of Exchanges, 2004).
2 Euronext is the merged stock exchange of former national exchanges of Belgium, France, Netherlands and Portugal. OMX owns and operates 7 exchanges based in the Nordic and Baltic countries. NYSE and NASDAQ are American stock exchanges with headquarters in New York. Borsa Italiana is the main Italian exchange and is located in Milan.
1 neighboring markets, such as the effect on relative market shares of European exchanges. The main motivation for studying liquidity is that it ultimately affects the cost of capital. For example, if trading volume of a particular stock is low, then the stock is harder to sell (e. in bear markets) and the bid-ask spread is typically high.
This makes the stock less desirable, which is reflected in price. Amihud and Mendelson (1986) estimate that the most illiquid stocks could gain 50% in value if, all else equal, liquidity would be raised to the level of the most liquid stocks. Brennan and Subrahmanyam (1996) and Datar et al. Liquidity is therefore of concern to both firms and the stock exchanges that serve them.3 The purpose of the study is to shed light on not only whether a stock exchange merger is beneficial to firms, but also how the gains may be distributed among market players.
Answering how liquidity has changed – and for which firms – is a valuable contribution to evaluating possible motives for stock exchange mergers and whether such mergers are advisable. A further motivation is to provide evidence on how a stock exchange merger may influence the competitive market environment, i. whether it proves to be an effective means of competition. In particular, it is of interest to explore whether merged exchanges attract market shares (share of trading) from other exchanges as a result of the merger - and if so, from which competing exchanges the additional order flow has been drawn.
Such competitive effects have largely been left unexplored in Europe. Empirical work directly related to stock exchange mergers is naturally limited in scope as there are still only a handful of realized mergers to be analyzed. Previous studies have therefore mostly been restricted to theoretical analyses or estimation of 3 For example, Aggarwal (2002) argues that the ability to generate trading volume will be a key factor in determining stock exchanges’ future success, since transaction revenue is likely to become the most important source of income. She argues that listing fees, revenues from sales of market data and membership fees are all likely to decrease due to competition among exchanges, technological innovation and members increasingly finding it advantegous to trade on multiple exchanges.
It should, however, be noted that more frequent trading may not be in the interest of investors (Barber and Odeon, 2000), even though firms benefit from more trading activity. Also note that no distinction is made between the type of trading (e. the focus is on quantity of trading rather than quality since the data does not detail the identity of traders. 2 cost functions of stock exchanges.4 On the empirical side, there are only a few papers that directly relate to this paper in terms of liquidity and stock exchange structure.
First, Jain (2003) examines 51 stock exchanges to pinpoint which institutional features are associated with higher liquidity. He finds that hybrid systems and pure electronic limit order books have better liquidity outcomes than e. pure dealer systems.5 Second, Arnold et al. (1999) analyze the effect of three U.
regional stock exchange mergers on liquidity and market share of exchanges. They find that merged stock exchanges provide narrower bid-ask spreads and attract market share from other exchanges. Their paper provides no firm heterogeneity analysis, but it applies the same econometric framework as used here for analyzing competitive effects of merger. Third, a noteworthy study by Padilla and Pagano (2005) analyses the effects of harmonization of clearing systems in the Euronext exchanges and finds that liquidity among the largest 100 stocks rose substantially.
Our study offers several significant improvements and extensions to the literature. In particular, the analysis is not restricted to a sub sample of firms. The paper introduces a comprehensive dataset including all firms listed on the four Euronext exchanges in 1996-2006. Having the whole population of firms offers a more complete picture of merger effects than studies limited to analyzing only a fraction of firms, typically the largest and most liquid ones.
The data richness also makes it possible to examine the potential heterogeneous outcomes of listed firms, which has not been viable in former studies with a non-random sub sample of firms. This paper is therefore a first step towards filling that gap by providing a far more direct and detailed analysis than previously offered. In other words, the heterogeneity analysis offers insight to the distributional effects of mergers such as which types of firms benefit from merger depending on characteristics such as firm size, industry, foreign 4 Among the latter are studies by Malkamäki (1999) and Schmiedel (2001), who argue that there are substantial economies of scale from integrating operations and eliminating duplication of fixed costs. Schmiedel et al.
(2002) extend this analysis to show scale economies in the settlement procedure, i. stock exchange integration should lead to higher trading volume which increases efficiency in the clearing and settlement mechanism. Theoretical papers include work by Santos and Scheinkman (2001) who present a model illustrating that competition among financial intermediaries will not lead to excessively low standards and may in some cases lead to better outcomes than monopoly. In contrast, Di Noia (2001) presents a model that demonstrates that mergers among exchanges are more efficient than competition, e.
due to network externalities. 5 A limit order market is a market where orders (which specify direction, quantity and acceptable price of trade) are compared to orders already held in the system (the book) and execution of trade takes place if there is a match between buy and sell orders. A dealer system is a market where an intermediary (the dealer) acts as a counterparty for the trades of his customer. A hybrid system is a combination of these two market systems.
3 exposure and location. The paper also examines four key merger events, i. it focuses not only on clearing system unification (the four key merger events are outlined in section 3). This provides a more detailed and comprehensive analysis of the effects of stock exchange merger, since such a merger is typically a lengthy process.
The study also includes firms from a handful of other European exchanges. This allows for improvement in the empirical methodology, such as the usage of control groups for robustness checks of results (i. extending time-dimensional event studies into a difference-in-difference estimation). The paper also estimates the competitive effects of the Euronext merger on other European stock markets.
Such a competitive analysis, i. the effect of stock exchange integration on non-merging markets, has not previously been carried out with European data. Finally, it should also be noted that the analysis of stock exchange merger is indirectly related to other categories of the financial literature. For example, several studies on stock market liberalization also deal with examining the effects of increased market size (number of potential investors) on liquidity (e.
Kim and Singal, 2000; Dahlquist and Robertsson, 2004). Also, the analysis of stock exchange mergers is related to studying cross-listings of firms, since firms tend to cross-list on bigger markets (and typically more liquid) than their home-market (Pagano et al.