This paper will examine the effects of inside information on bid-ask spreads when the probability of insider trading and the likelihood of an informational event occurring varies using a theoretical, simulation-based approach. The results show that bid-ask spreads narrow as the number of time periods increase, regardless of probability of insider trading or the likelihood of an informational event occurring. For a high, given likelihood of an informational event occurring, the highest average spreads were found for lower probabilities of insider trading as time increased. For a high, given probability of insider trading, the highest average spreads were found for lower likelihoods of an informational event occurring as time increased. The variances increased along with the probability of insider trading as well as with the likelihood of an informational event occurring. The maximum average spread settled near 0.25, typically found for a probability of insider trading of 1 and a likelihood of an information event occurring of 0.5. The results verify previous research done by Glosten and Milgrom (1985), Easley, Hvidkjaer and O’Hara (2002) and Potterton (2011). The results also may reconcile the differences between the findings of Easley, Hvidkjaer and O’Hara (2002) and Potterton (2011).

This paper will discuss arguments for and against the regulation of insider trading, examining economic discussions of efficiency and philosophical outlines of justice based arguments. I will also outline the development of legislation in the United States over the last century, and examine recent events in order to identify the current sentiments regarding government prosecution. The most efficient outcome for the market is found through actions guided by justice. By using regulation as a restraint to unbounded self-interest, investor confidence in the fairness of the market remains high and individuals are protected from abuses to their property and rights.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed October 15, 2009). PDF text: viii, 117 p. : ill. ; 1.43 Mb. UMI publication number: AAT 3355631. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (Ph. D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed July 31, 2007). Includes bibliographical references.

It is unfair to the investing public and detrimental to the interests of the security markets for a person to trade on the basis of inside information. In this short dissertation, the laws regulating insider trading in South Africa prior to the current legislative provisions are briefly discussed. It is found that the old provisions were inadequate in deterring and punishing insider trading activities. The current legislative provisions are analysed in detail. It becomes clear that whilst the current provisions are a substantial improvement on their predecessor, certain aspects need to be reconsidered. These include the widening of their scope to include trading in all kinds of derivatives; the reformulation of the statutory civil action and the empowerment of the securities regulation panel to bring a civil action against insider traders. / Private Law / LL.M.

abstract: Insider trading potentially reveals proprietary information, allowing rivals to compete more effectively against the insiders' firm. This paper examines whether proprietary costs are associated with insiders' trading decisions and the profitability of their trades. Using a variety of approaches to identify proprietary information risk, I find proprietary costs significantly deter insiders' trading activities. The deterrence effect is more pronounced when insider trading is likely to be more informative to rivals. Specifically, trades by top executives, non-routine trades, and trades at low complexity firms are curbed to a greater extent by proprietary costs. Examining the mechanisms of this deterrence effect, I find firms with higher proprietary costs are more likely to impose insider trading restrictions, and insiders' trading decisions are more sensitive to proprietary costs when they have higher share ownership of the company. These results suggest insiders reduce trading activities not only due to firm policies, but also due to incentive alignment. Finally, when insiders trade despite higher proprietary costs, they earn significantly higher abnormal profits from their purchase transactions. Overall, this study suggests product market considerations are an important factor associated with insiders' trading decisions and profitability of their trades. These findings are likely to be of interest to regulators and corporate boards in setting insider trading policies, and help investors make investment decisions using insider trading signals. / Dissertation/Thesis / Doctoral Dissertation Accountancy 2017

Dissertação (mestrado)—Universidade de Brasília, Universidade Federal da Paraíba, Universidade Federal do Rio Grande do Norte, Programa Multiinstitucional e Inter-Regional de Pós-Graduação em Ciências Contábeis, 2012. / Submitted by Alaíde Gonçalves dos Santos (alaide@unb.br) on 2013-01-23T14:40:26Z No. of bitstreams: 1 2012_LuizFelipedeAraujoPontesGirao.pdf: 1869594 bytes, checksum: 688211ddfd48f16b8e11f393e6c61362 (MD5) / Approved for entry into archive by Guimaraes Jacqueline(jacqueline.guimaraes@bce.unb.br) on 2013-02-04T12:42:59Z (GMT) No. of bitstreams: 1 2012_LuizFelipedeAraujoPontesGirao.pdf: 1869594 bytes, checksum: 688211ddfd48f16b8e11f393e6c61362 (MD5) / Made available in DSpace on 2013-02-04T12:42:59Z (GMT). No. of bitstreams: 1 2012_LuizFelipedeAraujoPontesGirao.pdf: 1869594 bytes, checksum: 688211ddfd48f16b8e11f393e6c61362 (MD5) / O objetivo dessa pesquisa foi analisar o efeito da assimetria informacional na avaliação de ações de empresas negociadas no mercado de capitais brasileiro. Foi necessário (a) avaliar as relações entre a assimetria informacional e os retornos das ações, (b) avaliar o value relevance das informações contábeis, e (c) comparar o value relevance das informações contábeis com e sem a adição de variáveis que mensurem a assimetria informacional. Recorreu-se, aos dados disponíveis de todas as empresas que negociaram suas ações na BM&FBovespa no período de 31/12/2009 a 31/01/2012. Para alcançar o objetivo desta pesquisa, foi utilizado um modelo de avaliação dos retornos das ações com a inclusão das variáveis beta, tamanho e book-to-market, por serem variáveis já testadas em pesquisas anteriores, como variáveis de controle, adicionadas as variáveis proxies para a assimetria informacional: índice de liquidez em bolsa (ILB), volatilidade do ativo (VOLAT), cobertura dos analistas de investimentos (COB) e a probabilidade de negociação com informações privilegiadas (PIN). Utilizando essas variáveis, em um modelo de dados em painel, foi encontrado que tanto o ILB quanto a VOLAT afetam os retornos das ações das companhias incluídas na amostra, implicando dizer que essas variáveis não são capturadas pelas outras variáveis descritas na literatura, confirmado quando se controla a liquidez da amostra, contudo apenas para a variável ILB. Foi verificado no presente trabalho, por meio do modelo de avaliação de empresas de Ohlson (1995) (MO), que o valor de mercado da firma pode ser explicado pelo patrimônio líquido e o lucro residual, concluindo que as informações contábeis são importantes para avaliação dos preços das ações no mercado brasileiro. Adicionalmente, buscou-se analisar o MO com a inclusão de variáveis proxies para “outras informações” (OI) ligadas à assimetria informacional. Esse modelo ajusta o lucro residual e OI aos seus parâmetros de persistência de modo a efetuar uma ligação entre as variáveis contemporâneas e as suas expectativas futuras. Na amostra completa, o lucro residual não se comportou de forma persistente, contudo, quando filtrado pela liquidez, encontrou-se um parâmetro de persistência de 0,1331, em média, indicando que os lucros residuais contemporâneos persistem à essa taxa. Já a persistência das OIs, na amostra completa ficou em torno de 0,5356, quando filtrada a amostra pela liquidez, essa taxa ficou em torno de 0,5009, indicando que aproximadamente 50% das variações das OIs de um período são explicadas pelas variações das OIs do período anterior, de modo que empresas com problemas de distribuição de informações tendem a continuar tendo os problemas. Finalmente, avaliou-se o impacto da assimetria informacional no valor da companhia, encontrando-se que, dependendo da amostra, o ILB, COB e a PIN se mostraram relevantes para a avaliação das empresas, disseminando informações ainda não divulgadas, de acordo com as teorias utilizadas como base para essa pesquisa (SPENCE, 1973; GROSSMAN; STIGLITZ, 1980). Diante dessas evidências, rejeita-se a hipótese de que a assimetria informacional auxilia na explicação dos retornos das ações e não se pode rejeitar a hipótese de que os números contábeis, em conjunto com a assimetria informacional, são relevantes para a avaliação das empresas. Os resultados obtidos nesse trabalho são limitados à sua amostra. _______________________________________________________________________________________ ABSTRACT / The purpose of this study was to analyze the effect of information asymmetry in the assessment of shares of companies traded on the Brazilian stock market. It was necessary (a) to evaluate the relationship between information asymmetry and stock returns, (b) assess the value relevance of accounting information, and (c) compare the value relevance of accounting information with and without the addition of variables that measure the informational asymmetry. We used the available data of all companies that traded their shares on the BM&FBovespa in the period from 31/12/2009 to 31/01/2012. To achieve the objective of this research, we used a valuation model of stock returns with the inclusion of variables beta, size and book-to-market, because they are variables already tested in previous research, as control variables, plus proxies variables for information asymmetry: liquidity ratio on the stock exchange (ILB), volatility of assets (VOLAT), analysts coverage (COB) and the probability of insider trading (PIN). Using these variables in a panel data model, it was found that both the ILB as VOLAT affect stock returns of companies in the sample, implying say that these variables are not captured by other variables described in the literature, confirmed when controls the sample for liquidity, but only for the variable ILB. It was found in this study through the Ohlson Model (1995) (OM), that the market value of the firm can be explained only by equity and residual income, concluding that accounting information is relevant for valuation of stock prices in the Brazilian stock market. Furthermore, we attempted to analyze the OM with the inclusion of proxies for “other information”(OI) associated with information asymmetry. This model adjusts the residual income and OI to its persistence parameters in order to make a connection between the contemporary variables and their future expectations. In the complete sample, the residual income behaved persistent, however, when filtered for liquidity, we found a persistence parameter of 0.1331, on average, indicating that the contemporary residual income persist to this rate. Since the persistence of OIs, in the complete sample was around 0.5356 when the sample filtered for liquidity, this rate was around 0.5009, indicating that approximately 50% of the variations of OIs a period are explained by variations in OIs from the previous period, so that companies with poor information distribution are likely to continue having problems. Finally, we assessed the impact of information asymmetry on the value of the company, finding that, depending on the sample, ILB, COB and PIN to be relevant to the valuation of companies, disseminating information not yet disclosed, according to the theories used as basis for this research (SPENCE, 1973; GROSSMAN; STIGLITZ, 1980). Faced with this evidence, rejects the hypothesis that the information asymmetry helps in explaining stock returns and we can not totally reject the hypothesis that the accounting numbers, together with the informational asymmetry, are relevant to the valuation of companies. The results of this study are limited to your sample.

Magister Legum - LLM / This study is on the insider trading framework of Tanzania. The researcher has made enquiries whether the Tanzania legal framework governing insider trading provides strong enough enforcement mechanisms, including remedies and measures against malpractices found on the securities market to attract investor confidence. Critical analysis is done of the Capital Markets and Securities Act, 79 of 1994 (RE 2002) in conjunction with an investigation into the Capital Markets and Securities Authority (CMSA) a body corporate charged with the duties among others, of protecting the integrity of the securities market and maintaining surveillance over securities to ensure orderly, fair and equitable dealings in securities. The researcher uses a comparative approach from other jurisdictions considered as international best standards of the English and South African insider trading legislation. Discussions on the study are presented in chapters. Chapter one is the general introduction to the Study. It is the reproduction of the research proposal. Chapter Two is on the overview of insider trading framework of Tanzania. An analysis is made on the provisions of the Capital Market and Securities Act, 79 of 1994 (RE 2002). It is revealed that the enforcement mechanisms are inadequate and ineffective. The Capital Market and Securities Act, 79 of 1994, (RE 2002) neither defines nor provides the interpretation to legal concepts such as insider, inside information and publication. Civil remedies and criminal penalties provided in the Tanzania Capital Market and Securities Act, 79 of 1994, (RE 2002) are inadequate for deterrent purposes to combat insider trading practices. In chapter three the researcher examines the Capital Market and Securities Authority (CMSA) in terms of fulfillments of its roles, functions, and powers. It is submitted that the CMSA and the DSE have never contributed much to resolving the problem of securities market abuses. Chapter four extend the study to the English and South Africa insider trading legislation considered as international best practice and therefore comparable. The researcher has observed that flaws in areas of prohibition, enforcements, defences and the lacuna on identified concepts of insider trading make the Tanzanian insider trading legislation remain more symbolic than real in terms of its efficiency to combating insider trading practices. Chapter five provides the conclusions and recommendations on the study. The researcher has provided recommendations on curbing the problem of insider trading in Tanzania, including repealing and enacting a new strong and effective insider trading legislation.

This thesis presents three models of asset pricing involving non-competitive behavior and asymmetric information. In the first model, a risk averse investor with private information about dividends trades shares over an infinite time horizon with risk neutral uninformed agents. The informed investor trades strategically in equilibrium. The second model also involves an infinite time horizon, but all agents are risk averse and equally informed about dividends. Non-competitive behavior is exogenously specified; price takers trade shares with a strategic investor who accounts for the effects of her trades on the stock price. In this case, an endogenous information asymmetry arises in equilibrium. Closed form equilibria are derived for both models and implications for price dynamics are explored. While the first model constitutes a new extension of the multiperiod Kyle model of insider trading, the second model generates more interesting price dynamics. If the strategic investor manages a large mutual fund, significant risk premia and price volatility may arise in equilibrium. In fact, if mutual fund participation is sufficiently widespread, multiple equilibria may exist. The third model extends the multiperiod Kyle model to a case where the insider observes a noisy signal of the stock's terminal liquidation value. An equilibrium much like Kyle's is derived. Price tends toward value over time, and stock price volatility depends on both the drift and volatility of the insider's private signal. Like the Kyle model, the insider's trading activity leaves no detectable trace in trading volume, expected returns, or price volatility. / Business, Sauder School of / Finance, Division of / Graduate

Abstract Title: Can outsiders obtain abnormal returns by imitating insider trading?- An application to trade in tech stocks on the Nasdaq Stockholm stock exchange.Comparing high and low volatile stocks. Course: JEFT27. Authors: Antonious Shalaby & Reis Rexha Advisor: Benjamin Miller Key Words: Insider trading, Abnormal Returns, Event Study Purpose:This study aims to investigate if there is a possibility of achieving abnormal returns foroutsiders on the stock exchange by following insider trading. This is being done with the goalof beating the index and outperforming the majority of the market, which has long been abenchmark for investors who are constantly developing new investment strategies byincorporating new variables of information. Methodology:The purpose of this study was achieved by utilizing a quantitative approach in conjunctionwith the Event Study model. We distinguished between high and low-volatility companies, asprevious studies had justified this. Subsequently, we conducted statistical tests to determine ifthe results were significant while also exploring the possibility of long-term effects throughseveral calibrations of the event window. Theoretical perspectives:To conduct this study, considerable attention has been given to prior research in the area,including the theory of the Efficient Market Hypothesis and the concept of Informationasymmetry. Empirical foundation:The insider trading that was analyzed took place between 2019-2022 in the thirty largesttechnology companies on the Nasdaq Stockholm Stock Exchange. Companies that did notmeet the requirements for the number of data points were excluded from the analysis. In total,twenty-six companies contained sufficient data. Conclusion:The study showed that there exists a possibility of obtaining abnormal returns. However, it isconstrained. To achieve this, the outsider must buy a highly volatile stock on the day the newswas published and sell it the day after. If the restrictions are not followed, we do not find thatabnormal returns are possible in the study.