This thesis investigates systematic liquidity risk and short-term stock price reaction to large one-day price changes. We study 642 constituents of the FTSALL share index over the period from 1st July 1992 to 29th June 2007. We show that the US evidence of a priced systematic liquidity risk of Pastor and Stambaugh (2003) and Liu (2006) is not country-specific. Particularly, systematic liquidity risk is priced in the London Stock Exchange when Amihud's (2002) illiquidity ratio is used as a liquidity proxy. Given the importance of systematic liquidity risk in the asset pricing literature, we are interested in testing whether the different levels of systematic liquidity risk across stocks can explain the anomaly following large one-day price changes. Specifically, we expect that the stocks with high sensitivity to the fluctuations in aggregate market liquidity to be more affected by price shocks. We find that most liquid stocks react efficiently to price shocks, while the reactions of the least liquid stocks support the uncertain information hypothesis. However, we show that time-varying risk is more important than systematic liquidity risk in explaining the price reaction of stocks in different liquidity portfolios. Indeed, the time varying risk explains nearly all of the documented overreaction and underreaction following large one-day price changes. Our evidence suggests that the observed anomalies following large one-day price shocks are caused by the pricing errors arising from the use of static asset pricing models. In particular, the conditional asset pricing model of Harris et al. (2007), which allow both risk and return to vary systematically over time, explain most of the observed anomalies. This evidence supports the Brown et al. (1988) findings that both risk and return increase in a systematic fashion following price shocks.

Denna studie visar utbetalningspolitiken hos företag noterade på Stockholmsbörsen år 2000-2015. Svensk utbetalningspolitik skiljer sig från utbetalningspolitiken i USA och inom EU. I Sverige fick återköp som utbetalningsform stor genomslagskraft år 2000 men trots detta är utdelningar fortsatt den dominerande utbetalningsformen idag. Vid en uppdelning i finansiella och industriella företag blir det tydligt att finansiella företag fått en allt mer betydelsefull roll inom svensk utbetalningspolitik. En ökad koncentration av det kassaflöde samtliga företag fördelar till aktieägare tycks inte kunna urskiljas på den svenska marknaden. Skiljer man på finansiella och industriella företag går det att se en ökad koncentration av det kassaflöde som fördelas av finansiella företag. År 2015 finns en stor andel mogna företag på Stockholmsbörsen vilket förklarar att total utbetalning av företag har ökat sedan 2000. Det framkommer genom att studera företagens kapitalstruktur och fas i den ekonomiska livscykeln. / This paper depicts payout policies of companies listed on the Stockholm Stock Exchange (SSE) 2000-2015. Payout policy in Sweden differs significantly from policy in the U.S. and the rest of the EU. In Sweden open market stock repurchases (OMR) came to be the dominant method of payout back in 2000. However, since then dividends have taken over the scene. Comparing financial and industrial corporations, makes it evident that financial corporations have come to gain prominence when it comes to shaping payout policy. It is not possible to entail an increasing concentration of cash flow that companies distribute to shareholders, when investigating the entire Swedish stock market. Dividing between the two sectors proves a heightened concentration of payouts among financial corporations. In 2015 mature companies have come to gain a greater share of SSE, which explains the increased number of dividend paying corporations since 2000. This becomes evident when examining the capital structure of the companies and their phase in the economic lifecycle.

Mémoire de recherche / Le krach chinois de l’été 2015 sur les Bourses de Shanghai et de Shenzhen est arrivé dans un moment de ralentissement de la croissance économique chinoise. De même, la décennie perdue (1989-2002) au Japon, qui a commencé par la chute des cours boursiers en décembre 1989, survient une année où la croissance économique avait ralenti d’une année sur l’autre. Afin de relativiser ces ralentissements, il faut savoir que la croissance du PIB chinois est passée de 7,27% à 6,9% entre 2014 et 2015 ; et que la croissance japonaise est passée de 7,15% à 5,37% entre 1988 et 1989. Ces niveaux de croissance sont plutôt exceptionnels dans l’histoire longue du capitalisme. Malgré le fait que ce soit bien des ralentissements de croissance que l’on observe, on n’en reste pas moins dans des économies en forte croissance. Alors pourquoi et comment ces crises sont-elles survenues ? À partir d’une analyse régulationniste des capitalismes chinois et japonais, on observe des transitions de régime de croissance qui s’opèrent dans les années 1970-80 au Japon et depuis 2008 en Chine. Ces transitions de régime suivent chacune une trajectoire particulière de libéralisation. Notre hypothèse est que plus une économie capitaliste se libéralise, c'est-à-dire que plus elle déréglemente ses marchés financiers plus elle observe de l’instabilité sur ses marchés. Autrement dit, nous cherchons à établir un lien entre le degré de libéralisation du secteur financier et la survenue de crises financières. En comparant la crise des années 1990 au Japon et le krach de l’été 2015 en Chine, on peut dire que la crise au Japon est une crise structurelle qui a énormément modifié le régime de croissance. En revanche, le krach chinois était une petite crise de liquidité sur les bourses causée en partie par de l’innovation financière (Ex. : opérations sur marge, dérivées, etc.) et un certain laisser-faire des régulateurs. En observant les différentes trajectoires de libéralisation des deux pays, on peut discerner deux trajectoires distinctes. En revanche, on observe deux dynamiques qui sont similaires, à savoir une ouverture graduelle des économies et une déréglementation du secteur financier au fur et à mesure que les deux pays s’érigent en grande puissance économique. De plus, les crises qui sont l’expression des contradictions intrinsèques à tout système capitaliste vont avoir pour effet de purger une partie des créances douteuses tout en maintenant une dynamique de libéralisation. Nos recherches ont montré que la libéralisation du secteur financier est bien responsable en partie de l’instabilité financière et donc de la formation de bulles qui finissent toujours par éclater, déclenchant ainsi des crises financières. / Both the Shanghai and Shenzhen stock markets crashed during the summer of 2015. This occurred at a time when China’s economy was slowing down. The same phenomenon occurred in Japan during the 1990s. What is commonly referred to as the Japanese « Lost Decade », began when stock prices declined in December of 1989, at a time when economic growth was losing strength. We can compare the declining growth in the economies of China and Japan for these respective periods: China’s economic growth diminished from 7.27% to 6.9% between 2014 and 2015; Japan’s economic growth diminished from 7.15% to 5.37% between 1988 and 1989. Notwithstanding the observed decline in both country’s economy, these growth figures can still be considered exceptionally strong in a capitalistic system. We are therefore confronted to economic slowdowns in fast-growing economies. This begets the question: What reasons explain these two financial crises? From the perspective of the « Théorie de la Régulation », a French school of political economy, transitions occurred in the growth regimes in both Japan and China. The genesis of the economic crisis observed in Japan was a consequence of contradictions proper to all capitalistic systems, a phenomenon that was observed during the 1970’s and 80’s. Similarly, the most recent turning point in China’s evolving form of capitalism, occurred as of 2008. Each of these countries’ growth regime transitions result from a different application of economic liberalization. Our working hypothesis is the demonstration that, as a capitalistic economy becomes more liberalized, that is to say, financial markets become less and less regulated, the greater the volatility in the markets. In other words, can it be affirmed that there exists a direct link between a liberalized financial activity and financial crises. In comparing the Japanese crisis during the ‘90s and the market crash in China during the summer of 2015, we can conclude that the root of Japan’s difficulty was structural in nature, whereas China simply had liquidity difficulties that can be attributed to two causes: innovative financial tools and risk-tolerant market activities. In fact, Chinese market regulators tolerated prohibited practices. There are also similarities in the liberalization of Japan and China’s financial markets. What we assert to be common to both countries’ pathway to market liberalization is openness to foreign investment and an increased international presence. In addition, both countries deregulated their financial sectors. These commonalities occurred as both countries became important economic players in the global economy. We also conclude that both crises, occurring, as stated previously, in a climate of increased market liberalization, allowed for the partial expungement of bad loans. However, it is undeniable that the liberalization of financial markets has as an intrinsic quality, that of market instability. Thus, the existence of financial crises.

Sammanfattning En omvänd aktiesplit ska inte ha någon direkt påverkan på ett företags värdering. Värdet är detsamma oavsett om företaget har fem utestående aktier á tjugo kronor eller en aktie á hundra kronor. Det är endast aktiepriset och antalet aktier som förändras. Dock kan informationen och genomförandet av en omvänd aktiesplit resultera i onormala reaktioner från investerare som får konsekvenser på aktiekursen, trots att själva händelsen är av en kosmetisk karaktär och kan definieras som icke-ekonomisk. Vilka effekter har då en omvänd aktiesplit på aktiekursen? Hur tolkar marknaden denna information? Och vilka motiv har företag till att genomföra en omvänd aktiesplit? Studien undersöker totalt 108 omvända aktiesplitar som genomförts på Stockholmsbörsen och First North Stockholm, under åren 2005 till 2018. Undersökningen sker genom en eventstudie och avvikande avkastning studeras på kort och lång sikt. Tidigare studier undersöker huvudsakligen två faser, annonsering samt genomförande. I denna studie undersöks fyra faser då företag presenterar information angående omvänd aktiesplit. Förslags-, besluts-, pressmeddelande- samt genomförandefasen. Anledningen till detta är för att kunna studera i vilken fas den kraftigaste marknadsreaktionen sker. Avvikande avkastning studeras baserat på splitfaktor. Utöver detta studeras även likviditet och risk både innan och efter genomförandet. De centrala teorierna som behandlas är prisintervall, effektiva marknadshypotesen och signalteori. Tidigare studier har visat att en omvänd aktiesplit generellt sätt resulterar i en negativ kursreaktion och medför en negativ avvikande avkastning. I denna undersökning finner vi likvärdiga resultat där den kraftigaste reaktionen sker vid genomförandet. Vi finner även en generell negativ avkastning under annonseringsfaserna, intressant är dock att den minsta reaktionen inträffar då den första informationen delges marknaden. En högre splitfaktor tenderar även att resultera i en mer negativ avvikande avkastning. På lite längre sikt tenderar aktiekursutvecklingen överlag att vara negativ. Undersökningens resultat visar även att både likviditet och volatilitet stiger efter genomförandet av en omvänd aktiesplit. Detta är inte helt i linje med tidigare studier då de generellt uppvisar en ökad likviditet men en minskad volatilitet. / Abstract A reverse stock split should not have any direct effect on a company’s valuation since the total value is the same whether the company has five stocks for twenty SEK each, or one stock for a hundred SEK. However, a reverse stock split tend to result in abnormal market reactions. This study investigates the effects on the stock price surrounding a reverse stock split and in the long run. The markets which are investigated are Stockholm Stock Exchange and First North Stockholm, during the period 2005 to 2018. Furthermore, the study examines whether abnormal returns exists around the announcement days and the ex-day, and if there is a connection between abnormal returns and split ratios. Liquidity and volatility changes due to the reverse stock split are also examined. The results show negative abnormal returns on the ex-day and the following days. On the announcement days there is also a general negative abnormal return, though not as substantial as during the ex-day period. A higher split ratio also tend to result in a more negative abnormal return. The study also finds that the liquidity and the volatility of the stock increases, following a reverse stock split. In the long run there is an overall negative Buy and Hold Abnormal Return (BHAR).

Em nosso trabalho analisamos os dados provenientes da BM&F Bovespa, a bolsa de valores de São Paulo, no período de janeiro de 2011, referentes aos índices: BOVESPA (IND), o mini índice BOVESPA (WIN) e a taxa de câmbio (DOL). Estes dados são de alta frequência e representam vários aspectos da dinâmica das negociações. No conjunto de valores encontram-se horários e datas dos negócios, preços, volumes oferecidos e outras características da negociação. A primeira etapa da tese foi extrair as informações necessárias para análises a partir de um arquivo em protocolo FIX, foi desenvolvido um programa em R com essa finalidade. Em seguida, estudamos o carácter da dependência temporal nos dados, testando as propriedades de Markov de um comprimento de memória fixa e variável. Os resultados da aplicação mostram uma grande variabilidade no caráter de dependência, o que requer uma análise mais aprofundada. Acreditamos que esse trabalho seja de muita importância em futuros estudos acadêmicos. Em particular, a parte do carácter específico do protocolo FIX utilizado pela Bovespa. Este era um obstáculo em uma série de estudos acadêmicos, o que era, obviamente, indesejável, pois a Bovespa é um dos maiores mercados comerciais do mundo financeiro moderno. / In our work we analyzed data from BM&F Bovespa, the stock exchange in São Paulo. The dataset refers to the month January 2011 and is related to BOVESPA index (IND), mini BOVESPA index (WIN) and the exchange tax (DOL). These, are high frequency data representing various aspects of the dynamic of negotiations. The array of values includes the dates/times of trades, prices, volumes offered for trade and others trades characteristics. The first stage of the thesis was to extract information to the analysis from an archive in FIX protocol, it was developed a program in R with this aim. Afterwards, we studied the character of temporal dependence in the data, testing Markov properties of a fixed and variable memory length. The results of this application show a great variability in the character of dependence, which requires further analysis. We believe that our work is of great importance in future academic studies. In particular, the specific character of the FIX protocol used by Bovespa. This was an obstacle in a number of academic studies, which was, obviously, undesirable since Bovespa is one of the largest trading markets in the modern financial world.

A tese a ser defendida é a de que a autorregulação institucionalmente estruturada e legitimada pela regulação é um eficiente arranjo para tratar as falhas e riscos inerentes ao mercado de bolsa. O trabalho se inicia com a descrição da atual estrutura da autorregulação do mercado de bolsa, destacando seu novo formato institucional decorrente do processo de desmutualização e abertura de capital das entidades administradoras do mercado de bolsa e concluindo pela necessidade de adoção de novas perspectivas sobre o tema que transcendam o aparente antagonismo entre concepções liberais e intervencionistas. A partir dessa premissa, o trabalho apresenta uma visão panorâmica da evolução histórica da autorregulação do mercado de bolsa e considerações sobre os conceitos de autorregulação em outras áreas do conhecimento, a fim de identificar suas variações e seus elementos mais marcantes que constituirão a base a partir da qual serão apresentadas as novas perspectivas de análise do tema. As perspectivas propostas enfocam a natureza jurídica da autorregulação do mercado de bolsa como atividade paraestatal destinada a concretizar o modelo teórico neoclássico de justa formação dos preços segundo a livre atuação das forças de oferta e demanda e, também, melhorar os padrões de conduta praticados no mercado. Para tanto, o trabalho propõe que as decisões tomadas no âmbito da autorregulação se pautem por critérios materiais baseados nas premissas teóricas da concorrência perfeita e na exigência de cumprimento dos deveres derivados da boa-fé objetiva (informação, lealdade e proteção). Por fim, é apresentada uma especulação teórica, preliminar e não definitiva, denominada teoria palco-platéia, que visa situar o desenvolvimento da estrutura de autorregulação do mercado de bolsa como parte de uma questão essencial de interação entre indivíduo e sociedade representada nas diversas situações comunicativas envolvidas nos processos decisórios individuais e coletivos que modelam os padrões de conduta e as instituições públicas e privadas. / The thesis to be defended is that the institutionally structured self-regulation and legitimized by the regulation, is an efficient array to treat flaws and risks inherent of the exchange market. The paper begins with a description of the current self-regulation structure of the exchange market, highlighting its new institutional format, due to the demutualization process and IPO of the entities that manage the exchange market, and concluding with the need of the adoption of new perspectives regarding the subject-matter that transcend the apparent antagonism between liberal and interventionist conception. From this premise, the paper presents an overview of the history of self-regulation of the exchange market and considerations on the concepts of self-regulation in other areas of knowledge, for the purpose of identifying its variations and its most striking elements that will form the basis from which the new perspectives of analysis of the matter will be presented. The proposed views focus on the legal nature of the exchange markets self-regulation as a parastatal activity that seeks to achieve the neoclassic theoretical model of fair pricing, according to the free action of forces of supply and demand, and also improve the conduct standards in the market. Therefore, the paper proposes that decisions made within the self-regulation should be guided by material criteria based on theoretical postulations of perfect competition and in the requirement of the obligations derived from the objective good faith (information, loyalty and protection). Lastly, a preliminary and not final, theoretical speculation is presented, denominated stage-audience theory, which aims to situate the development of the self-regulation structure of the exchange market, as part of an essential matter of interaction between individual and society represented in various communication situations involved in individual and collective decision-making, which shape the standards of conduct, and public and private institutions.

Made available in DSpace on 2016-04-26T20:48:50Z (GMT). No. of bitstreams: 1 Luiz Eduardo Costa e Silva.pdf: 304575 bytes, checksum: 09df8ddf3c7d01fa9e7bda58c6cabe5f (MD5) Previous issue date: 2007-12-19 / This paper analyzes the vigorous expansion of the stock market in Brazil in recent years. Along with a substantial increase in liquidity and the strong rise in value of shares traded, there has been a renewed trend for companies to go public and obtain funding for investment through IPOs, with a significant increase in foreign and institutional investors' shares of the trades made on the São Paulo Stock Exchange (Bovespa). The relevance of this process poses the relations between financial development and economic growth, especially the growth in private sources of financing for corporate investment, which has characteristically been insufficient in Brazil's history of financial development. In addition to characterizing the process now underway, the paper points to its main determinants: in terms of macroeconomic factors, the strong inflow of funds improved Brazil's foreign currency reserves, control of inflation and lower interest rates; in terms of institutional factors, the improved stock market regulatory framework was reflected in the reform of laws governing the capital market and the work of the Brazilian Securities and Exchange Commission, with acceptance of corporate governance concepts for special listing segments on Bovespa as standards to be followed by issuers . This set of changes on several levels shows that there has been a turning point after which the stock market has started to play a key role in financing investment, and therefore in the economic development of Brazil. The consolidation of this process depends on preserving the advances obtained, continuously improving financial system institutions, and correcting any deficiencies identified / A dissertação analisa a vigorosa expansão do mercado de ações no Brasil nos últimos anos. O expressivo incremento da liquidez e a forte valorização dos papéis negociados foram acompanhados pela retomada dos processos de abertura de capital das empresas e a obtenção de recursos para investimento em ofertas públicas primárias, com aumento significativo da participação dos investidores estrangeiros e institucionais nos negócios realizados na Bolsa de Valores de São Paulo Bovespa. A relevância deste processo está ligada às relações entre desenvolvimento financeiro e crescimento econômico, em especial a ampliação das fontes de financiamento privadas para o investimento das empresas, caracterizadas como insuficientes no desenvolvimento financeiro do Brasil. Além de caracterizar o processo em andamento, o trabalho aponta seus principais determinantes: pelo lado dos fatores macroeconômicos, a forte entrada de recursos externos, a melhoria da posição cambial do país, o controle do processo inflacionário e a redução das taxas de juros; pelo lado dos fatores institucionais, o aperfeiçoamento do marco regulatório do mercado de ações, refletido na reforma das leis que regem o mercado de capitais e na atuação da Comissão de Valores Mobiliários, e na aceitação dos conceitos de governança corporativa dos segmentos especiais de listagem da Bovespa como padrões a serem seguidos pelos emissores de ativos. Este conjunto de mudanças em diversos planos indica ocorrência de um ponto de inflexão a partir do qual o mercado de ações passou a ocupar posição de destaque no financiamento dos investimentos e, por extensão, no desenvolvimento econômico do Brasil. A consolidação deste processo depende da preservação dos avanços obtidos, do aperfeiçoamento contínuo das instituições do sistema financeiro e da correção de deficiências identificadas

This study examines Ludwig Zinzendorf’s political economy and the intellectual inspiration of his thinking. Zinzendorf, a protégé of Kaunitz, was a sophisticated economic thinker in the mid eighteenth-century Habsburg monarchy who was part of the wider intellectual movement in Europe dedicated to understanding political economy and presenting it as an independent and important activity. Self- educated, polyglot and hard-working, Zinzendorf was formidably well read and impressively numerate. His output was detailed and analytical. With an exceptionally wide knowledge, he offered a more original way to discuss the economy than the essentially didactic approach of cameralist writers. He was a reformer dedicated to propagating the most advanced European ideas and practices. This study is divided into five chapters: chapter one covers the relationship between Zinzendorf and Kaunitz and Zinzendorf’s formative years in France from 1750 to 1752. The influence of French economic thinkers on Zinzendorf’s intellectual development, Jean-François Melon and Vincent de Gournay in particular, is the subject of chapter two. Chapter three is devoted to Zinzendorf’s German translation of John Law’s Money and Trade. The development of Zinzendorf’s ideas on state credit, notably the creation of a new stock exchange and political bank in the monarchy, modelled on the Bank of England, is discussed in chapter four. The final chapter examines how Zinzendorf operated as a sophisticated financial expert in the monarchy. He sought to provide a different kind of economic advice and attempted to open-up government to new concepts on the economy. He was influenced by the important contribution in France made by Gournay and his circle of writers in disseminating foreign ideas by publishing in French a range of economic texts from rival nations. Zinzendorf, it is argued, attempted to apply a moderate format of Gournay’s initiative in the monarchy.

O fortalecimento de um mercado acionário está relacionado diretamente com a transparência e confiabilidade da informação disponível para os usuários desses mercados. Com este fim, o auditor e o seu trabalho, divulgado através do relatório de auditoria, configuram-se como garantias da realidade econômica e contábil das empresas de capital aberto. No entanto, na realidade latino-americana (nos casos do Brasil, Colômbia e Argentina), ainda não se tem quantificado o impacto que o auditor, e o relatório de auditoria, exercem na dinâmica dos seus mercados acionários. Em resposta à falta de estudos que quantifiquem a relação auditoria mercado acionário se formula o presente trabalho. Assim, analisa-se, através de um estudo de eventos, o efeito que os relatórios de auditoria exercem no preço das ações das companhias de capital aberto listadas nas principais bolsas de valores do Brasil (Bolsa de Valores, Mercadorias e Futuros BM&F Bovespa), Colômbia (Bolsa de valores de Colombia BVC) e Argentina (Bolsa de Comercio de Buenos Aires BCBA). Realizou-se um estudo univariável e multivariável para testar as hipóteses. No caso brasileiro e argentino, o período de estudo abrangeu desde o ano 2000 até 2007. No primeiro caso, confirma-se que a divulgação dos relatórios de auditoria modificados, das companhias de capital aberto participantes da BM&FBOVESPA, não afeta o preço das suas ações. Já para o caso da Argentina, obtém-se um resultado oposto, verificando através do teste de hipóteses que o relatório do auditor impacta no mercado acionário representado pela Bolsa de Comércio de Buenos Aires; em particular, a divulgação dos relatórios de auditoria modificados tem um efeito negativo nos preços das ações negociadas no mercado acionário Argentino. Por último, no mercado acionário da Colômbia analisa-se um período de estudo desde o ano 2001 até 2007. Na Colômbia são obtidos resultados similares aos verificados no mercado acionário brasileiro. Assim, a contribuição do presente trabalho é avaliar e quantificar a importância do auditor externo nesses países em estudo e, indiretamente, avaliar o uso do relatório de auditoria como médio de divulgação de informação relevante aos seus mercados acionários. / The strength of a stock market is related to transparency and reliability of all information available for its users. In this sense, both the auditor and his work, which is disseminated through the auditing reports, become the guarantee of the economical reality from all publicly traded companies. However, in Latin America reality (especially in Brazil, Colombia and Argentina), the impact of the Auditor and his reports still has not been verified upon the stock markets. Hence, this present job aims to respond to the lack of studies stating the relationship between Auditing and Stock markets in Latin America. The analysis is done through a event study, evaluating what is the auditing report effect upon the prices of stocks from the main publicly traded companies in Brazilian stock market (Bolsa de valores, Mercadorias e Futuros BM&FBovespa), Colombian stock market (Bolsa de valores de Colombia BVC) and Argentine stock market (Bolsa de Comercio de Buenos Aires BCBA). In particular, two studies are carried out, one univariable and the other multivariable, in order to test the hypothesis. In Brazilian and Argentine cases, the study covers the period from 2000 until 2007. In the first case, the disclosure of the modified auditing reports, considering public companies of the BM&FBovespa Stock Exchange, does not affect their stock price. On the contrary, in Argentine case, an opposite result is obtained: the auditing reports impact on BCBA Stock Exchange; specifically, the disclosure of modified auditing reports has a negative effect on stock prices. Finally, for the Colombian stock market, a study period from 2001 until 2007 is utilized. In Colombian case, similar results to those reported from Brazilian analysis are obtained. The contribution of this thesis is to evaluate and quantify the role of the auditor in the countries mentioned above and, indirectly, the use of the auditor\'s report as way to disseminate Auditing information.

O fortalecimento de um mercado acionário está relacionado diretamente com a transparência e confiabilidade da informação disponível para os usuários desses mercados. Com este fim, o auditor e o seu trabalho, divulgado através do relatório de auditoria, configuram-se como garantias da realidade econômica e contábil das empresas de capital aberto. No entanto, na realidade latino-americana (nos casos do Brasil, Colômbia e Argentina), ainda não se tem quantificado o impacto que o auditor, e o relatório de auditoria, exercem na dinâmica dos seus mercados acionários. Em resposta à falta de estudos que quantifiquem a relação auditoria mercado acionário se formula o presente trabalho. Assim, analisa-se, através de um estudo de eventos, o efeito que os relatórios de auditoria exercem no preço das ações das companhias de capital aberto listadas nas principais bolsas de valores do Brasil (Bolsa de Valores, Mercadorias e Futuros BM&F Bovespa), Colômbia (Bolsa de valores de Colombia BVC) e Argentina (Bolsa de Comercio de Buenos Aires BCBA). Realizou-se um estudo univariável e multivariável para testar as hipóteses. No caso brasileiro e argentino, o período de estudo abrangeu desde o ano 2000 até 2007. No primeiro caso, confirma-se que a divulgação dos relatórios de auditoria modificados, das companhias de capital aberto participantes da BM&FBOVESPA, não afeta o preço das suas ações. Já para o caso da Argentina, obtém-se um resultado oposto, verificando através do teste de hipóteses que o relatório do auditor impacta no mercado acionário representado pela Bolsa de Comércio de Buenos Aires; em particular, a divulgação dos relatórios de auditoria modificados tem um efeito negativo nos preços das ações negociadas no mercado acionário Argentino. Por último, no mercado acionário da Colômbia analisa-se um período de estudo desde o ano 2001 até 2007. Na Colômbia são obtidos resultados similares aos verificados no mercado acionário brasileiro. Assim, a contribuição do presente trabalho é avaliar e quantificar a importância do auditor externo nesses países em estudo e, indiretamente, avaliar o uso do relatório de auditoria como médio de divulgação de informação relevante aos seus mercados acionários. / The strength of a stock market is related to transparency and reliability of all information available for its users. In this sense, both the auditor and his work, which is disseminated through the auditing reports, become the guarantee of the economical reality from all publicly traded companies. However, in Latin America reality (especially in Brazil, Colombia and Argentina), the impact of the Auditor and his reports still has not been verified upon the stock markets. Hence, this present job aims to respond to the lack of studies stating the relationship between Auditing and Stock markets in Latin America. The analysis is done through a event study, evaluating what is the auditing report effect upon the prices of stocks from the main publicly traded companies in Brazilian stock market (Bolsa de valores, Mercadorias e Futuros BM&FBovespa), Colombian stock market (Bolsa de valores de Colombia BVC) and Argentine stock market (Bolsa de Comercio de Buenos Aires BCBA). In particular, two studies are carried out, one univariable and the other multivariable, in order to test the hypothesis. In Brazilian and Argentine cases, the study covers the period from 2000 until 2007. In the first case, the disclosure of the modified auditing reports, considering public companies of the BM&FBovespa Stock Exchange, does not affect their stock price. On the contrary, in Argentine case, an opposite result is obtained: the auditing reports impact on BCBA Stock Exchange; specifically, the disclosure of modified auditing reports has a negative effect on stock prices. Finally, for the Colombian stock market, a study period from 2001 until 2007 is utilized. In Colombian case, similar results to those reported from Brazilian analysis are obtained. The contribution of this thesis is to evaluate and quantify the role of the auditor in the countries mentioned above and, indirectly, the use of the auditor\'s report as way to disseminate Auditing information.