Nowadays, about one fourth of all prime time commercials in the United States feature celebrity endorsers. Previous research has identified numerous benefits of this powerful marketing strategy. Unfortunately, celebrities have been increasingly involved in negative publicity in the recent past. Using event study methodology, I examine the influence of negative celebrity endorser publicity on immediate and subsequent stock returns, covering 59 events during a 25 year period from 1988 to 2012. My research shows that firms do not have to take losses for granted. By choosing proactive versus reactive/passive strategies, firms can successfully counteract the subsequent negative stock returns. Thus, it is not the negative event itself that drives the subsequent financial performance, but rather the immediate response of firms. Although immediate firm reactions increase the salience of the event and cause stock prices to drop initially, they also build up investors' trust and confidence again, ultimately leading to increased stock returns in the subsequent weeks. On the flipside, a reactive/passive strategy shows a lack of control and leadership, which can lead to substantial financial losses in the subsequent weeks. I show that this main effect is attenuated for subsidiary (vs. corporate) brands. Further, the appropriateness of the reaction (match between expected and actual firm reaction) is also crucial. Overall, this dissertation helps to advance the knowledge regarding the financial risk of negative celebrity endorser publicity and provides firms with advice to best manage the situation. / Ph. D.

Mergers and acquisitions (M&A) play an important role in shaping the landscape of modern business, helping companies reach new customers, drive growth, and capitalise on synergies. Simultaneously, the recognition of Environmental, Social, and Governance (ESG) has experienced a rapid escalation, prompting companies to incorporate ESG into their operational frameworks. As a result, investors become keen to understand how these factors affect the financial valuation, particularly within the context of M&A. This study examines the influence of ESG factors on stock market reactions around M&A announcements. Through a quantitative analysis of M&A events spanning from 2010 and 2024, it investigates the impact ESG scores have on cumulative abnormal returns (CAR). The findings reveal that the short-term average return of an M&A announcement is negative and that ESG scores themselves do not exhibit a significant impact on the CAR. However, interacting ESG scores with different industries show significant effects. In sectors such as energy and power, high technology, and material, ESG has a significant positive effect, while the financial sector yields a negative result on CAR. It can be concluded that the effect of ESG on CAR is dependent on the industry, suggesting that sectors who are sensitive to sustainability have more pressure to perform, thereby yielding a higher positive return upon announcement.

Whether insiders can use informational advantage when purchasing or selling their company stocks to generate cumulative abnormal returns (CAR) has shown different results in several markets. The Swedish market is yet to be extensively examined, and this thesis aims to understand how insiders in the OMXS30 companies perform when testing CAR and if there exists an information asymmetry. A predicted return is generated through the market model to calculate CAR, and the same index OMXS30 is combined with stock return data. We conducted an event study through Stata to match the transactions with a particular trading day to see how the insiders' transaction yielded CAR. We find that significant CAR exists for all insider groups for various event windows and find a difference in significant CAR for both genders and insider positions. The results were robust when we changed to a new market index as the independent variable in our regression analysis. The results align with previous literature, stating that insiders generated significant CAR from insider trading and differences between insider position and gender (Jeng et al. 2003; Jiang & Zaman, 2010; Lasfer & Ye, 2023). The findings can be used for regulatory purposes when investigating information asymmetry.

Background: In financial markets, decisions to buy or sell securities are highly influenced by the aim of making a profit and avoiding losses. The signals that insider transactions send to external investors can significantly impact those decisions. The signals can differ depending on the type of transaction, within which sector, and the company's size. Purpose: The purpose of this thesis is to investigate whether insider transactions employ a more potent influence when buying or selling stocks. A partial purpose is distinguishing between small- and mid-cap stocks and between the technology and industrial sectors on the Nasdaq Stockholm Stock Exchange. Methodology: A quantitative approach was utilised with the event Study model. Hypotheses were constructed, and statistical tests in STATA were conducted to determine if the results were significant. The insider trading that was analysed took place between 2018-2023. Thirty-one companies are in the industrial sector, and twenty-eight are in the technology sector, with 3601 insider transactions employed. Conclusion: The results showed the existence of signalling effects and the possibility of achieving abnormal returns, especially if shorting when insiders are selling, particularly technology stocks, with the most prominent returns from mid-cap firms. However, the results contradict most previous research proposing that purchase transactions yield higher abnormal returns and have a more substantial signalling effect.

The Riksbank’s purpose with the policy rate is to create price stability in the economy and achieve the inflation target. The Swedish real estate market is interest rate sensitive, thereby affected by the economy in Sweden. This thesis investigates the policy rates impact on the volatility of the Swedish real estate market, during the years 2002-2024, using an event study approach with panel regressions. Further, if an increase or decrease of the policy rate have a greater impact of the volatility. By using a quantitative method this thesis uses historical data representing each firm as well as some other independent variables, as OMX Stockholm Real Estate GI. The study provided evidence that the policy rate has an impact on the volatility of the Swedish real estate market, as the majority of the events demonstrated a relationship between the policy rate and the volatility. However, the thesis could not conclude if an increase or decrease of the policy rates has had a greater impact.

Does the stock prices of oil companies affected by the announcement of a corporate name changes? This paper investigates the North American oil firms undergo name changes from 2000 to 2005. We report a significantly positive abcdrmal return (12.5%) and abcdrmal trading volume on the event day for the overall 125 companies in our sample. During the period of crude oil price surges after 2004, we find a tendency of increasing number of firms add oil to their corporate names to signal their links with the oil markets. In the U.S., the CARs of firms add oil in their corporate names show positive effects on their stock prices. Their pre-event excess returns are not offset by post-event drift, especially in the oil hot period. Interestingly, we find that firms delete oil names in the oil hot period suffer a significant negative CAR in the post-event period. We provide evidence that major name changes are more beneficial than minor name changes in the North America oil companies, and name changes affect stock prices more positively for smaller companies than for big firms on event day. Between the U.S. and Canada, we show that there are the different CAR trends for each country. The information leakage period is longer in Canada than the U.S. It is seen that a firm with a resource unrelated activities adds an oil name, it would earn a permanent CAR. The overall results in our study suggest that the announcement of corporate name changes of oil companies convey important information to the stock market regarding their corporate images and identifies. Investors appear to respond enthusiastically to the word “oil” in corporate names because of the relationship with a glamorously lucrative and potentially growing oil prices.

本文主要目的是在探討，當企業決定其融資方式，改變資本結構後，究竟是否會造成投資人對該企業經營獲利前景的改變，而反應在企業的股票價格上，尤其在「不同聯貸資金用途」上，是否會改變投資人、股東對於該企業風險程度的認定。本文利用事件研究法(Event Study Method)進行分析，研究期間自2005年至2007年止，針對台灣上市(櫃)公司完成聯貸簽約資料，刪除估計期未滿160天者後，有效樣本共140筆，其中營運週轉金(Working Capital)資金用途者有36筆；借新還舊(Refinancing)資金用途者有71筆；資本支出(Capital Expenditure)資金用途者有33筆。 本研究之實證結果發現，若資金用途為營運週轉金者，於聯合貸款宣告後，並沒有顯著異常報酬差異；若資金用途為借新還舊者，於聯合貸款宣告後，具有顯著的正向異常報酬差異；若資金用途為資本支出用途者，於聯合貸款宣告後，具有顯著負向異常報酬差異。 關鍵詞：聯合貸款、事件研究法、異常報酬 / The main purpose of this study is to discuss whether investors will change their anticipation on the perspective of a company, which is reflected on its stock price when the company decides on its financing method and thus changes its capital structure, and especially whether investors and shareholders will change their recognition on risk-taken levels of the company in light of different purposes of syndicated loans. This study employs Event Study Method and focuses on the listed and over-the-counter companies in Taiwan dated from Year 2005 through Year 2007. The valid sample size amounts to 140 companies after removing those companies whose estimation period is less than 160 days. Of the 140 sample companies, 36 are working capital related, 71 are refinancing related, and 33 are capital expenditure related. The empirical results of this study indicate that, upon announcement of syndicated loans, there are no significant positive abnormal returns if the loans are used as working capital, there are significant positive abnormal returns if the loans are used as refinancing, and there are significant negative abnormal returns if the loans are used as capital expenditure.

This paper investigates the impact of corporate name changes on both of stock performance and analysts’ reaction with the employment of event study. We first examine a sample of 387 listed Australian companies that renamed themselves during the time frame from January 2001 to December 2007. Separate analyses are conducted under three criterion dividing the overall sample into (1)”major” versus “minor” name changes; (2)name changes in “mining-related” versus “non-mining-related” sectors; and (3)name changes “with” versus “without” reasons mentioned. Generally, we find some evidence of significant negative association between corporate name changes and cumulative abnormal return. The result shows, unlike all other subgroups, name changes “with” reasons mentioned generate insignificant positive valuation effects. Separate analyses give two important implications. First, negative cumulative abnormal return in all subgroups is discovered except in the subgroup of name changes “with” reasons mentioned. The difference of abnormal returns within subgroups, in addition, appears to be significant only between name change with reasons mentioned or not. Our findings suggest that analysts react reluctantly to corporate name changes by showing tiny downward forecast revisions, which are far from significant. Instead, it seems analysts make forecast revisions based more on accounting data, which shows insignificant variations between pre- and post-event, than on signals of corporate name changes.

Syfte: Studiens syfte var att undersöka om det uppstår onormal avkastning för målföretagets aktieägare vid offentliggörandet av företagsförvärv på den svenska aktiemarknaden, samt att undersöka om den svenska aktiemarknaden är effektiv enligt den effektiva marknadshypotesen. Metod: I uppsatsen tillämpades en eventstudie för att studera den onormala avkastningen. Datainsamlingen har skett från Thomson Reuters Eikon, Orbis, Zephyr och Retriver. Studiens dataunderlag har analyserats och presenterats i figurer och tabeller. Resultatet bygger på hypotesprövning och signifikanstest av framräknade onormala avkastningar.  Resultat & slutsats: Resultatet visade att målföretagens aktieägare vid offentliggörandet av företagsförvärv i genomsnitt erhöll en hög positiv onormal avkastning under perioden 2011 till 2016, samt att den svenska aktiemarknaden var effektiv. Detta genomsnittliga värde var statistiskt signifikant på signifikansnivån 0,01 procent. Förslag till fortsatt forskning: Ett förslag till vidare forskning är att undersöka ett längre tidsspann, vilket kan öka populationens storlek. Vidare forskning kan även undersöka om olika faktorer i företagsförvärvet kan förklara de erhållna onormala avkastningarna.  Uppsatsens bidrag: Studien bidrar med relevant information till företagsledningar, finansanalytiker och företagsintressenter. Detta eftersom studiens resultat skapar förståelse för företagsförvärv i en svensk kontext och kan därför ligga till grund för beslutsfattande, värderingar och beräkningar av framtida företagsförvärv. / Aim: The aim of the study is to examine if the target company shareholders receive an abnormal return on the day of the announcement, on the Swedish stock market. The study also examines if the Swedish stock market is efficient according to the efficient market hypothesis. Method: The study was conducted according to the event study methodology. The data was collected from Thomson Reuters Eikon, Orbis, Zephyr and Retriever. The findings in the study was displayed and analysed in figures and tables. Hypothesis test and test of significance were used to investigate the aim of the study. Findings and conclusions: For the time period studied, 2011 to 2016, the target company shareholders on average received a high positive abnormal return on the day of the announcement, which was significant on the one percent level. The findings also indicates that the Swedish stock market is efficient according to the efficient market hypothesis. Suggestions for future research: One suggestion for future research could be to expand the time interval, which could increase the size of the population. Future research could also take the characteristics of the acquisition in consideration in an attempt to explain the abnormal returns found in this study.  Contribution of the thesis: This study’s findings are relevant for the chairmen of the board, finance analysts and corporate stakeholders. The findings in this study provides an understanding of the nature of acquisitions on the Swedish stock market, which can be used for decision making, evaluations and calculations of future acquisitions.

This paper treats the question about how the internationally established company, Apple, is affected by intern or extern events when it comes to the trade market. The purpose of the study is to investigate if chosen events create abnormal return on Apples stock market. The chosen research area is Steve Jobs three sick-listings, It-bubble and the purchase of the search engine company Siri. The reason of writing about this is the big interest for the stock market and its function. This study methodological starting position is quantitative done by an event study, with qualitative feature done by an interview with an expertise within this area. When analyzing the empirics, we have used the efficient market theory that says that information should not affect the stock market in the degree that abnormal return creates. Beyond that theory, we have used former research "Stock prices and top management changes" written by Jerold B. Warner and Ross L. that got abnormal return when they did an event study about CEO changes, "CEO change and firm performance in large corporations: succession effects and manager effects", Randolph P. Beatty och Edward J. Zajac. that means that the stock prices affect is different depending on if the shareholders is more prepared to the information, "The stock market psychology" there Gyllenram refers to his theory about people projecting their thoughts and feelings to each other that creates big movements on the stock market and "Beyond Greed and Fear", Shefrin H. that while his study discovered a new theory that he called "the opposite strategy", meaning that a high positive volatility is comply with a negative volatility by the same value. Shefrin also note that new information makes overreaction and vice versa. The conclusion that we can make by this research is that new shocking information has led to overreaction, exactly like Shefrin points out. That means that older information makes less volatility, and we can see this by studying Steve Jobs three sick-listings. The efficient market theory was adaptable on these three events, because abnormal return did not occur. However, we got abnormal return on the other two events, Siri and the It -bubble. We could associate these answers to Shefrin´s theory about overreaction when new information gets public.