none

¡@¡@Treasury stock system allows listed companies to buy back their own shares in the open market. In general, when the company announced stock repurchase event, investors are optimistic about the prospects of the company. Therefore, the company's stock price usually rises. But will investors buy more stocks, leading to increased liquidity of stocks? This study combines with stock repurchase and liquidity to investigate the impact of stock repurchase on liquidity. Further events will be studied by different factors stratified, including firm size, stock price, industry, the purpose of stock repurchase, the proportion of execution, the holding ratio of insiders and institutional investors. By using three types of liquidity measures, the study is to observe the changes of liquidity of stocks in the different situations. ¡@¡@After conducting mean difference in pair-sample test, the empirical results indicate that the sample stocks in the stock repurchase announcement, the outcome supports liquidity increase hypothesis. In terms of the stratification factors, the smaller of the company size or lower stock price will help increase the liquidity of the stock in the market. Non-electronics sector, aims to buy back equity write-off shares can improve market liquidity. Higher or lower percentage of insider ownership shares in¡@companies will lead to the increase of stock liquidity. Higher holding shares proportion of institutional investor in companies will increase liquidity. The amount of execution ratio is of no factors, but the liquidity of the stock repurchase still supports the liquidity increase hypothesis.

Firms that announce open-market share repurchase programs are not obligated to follow through in the actual acquisition of shares. In fact, we find that the majority of firms fail to acquire the target number of shares specified at announcement and many firms fail to repurchase any shares at all. Therefore, the announcement of a share repurchase program has a degree of uncertainty regarding the announcing firms credibility. This study examines the possibility that market participants evaluate the credibility of a firms share repurchase announcement based on the firms previous share repurchase history. We examine 1,507 share repurchase programs for firms listed on the Toronto Stock Exchange (TSX) from 1995 to 2005 and find that firms that have completed a higher proportion of previous share repurchase programs experience larger abnormal returns on the announcement of subsequent repurchase programs. Therefore, we conclude that the market reacts more favorably to the share repurchase announcements of credible firms compared to firms that lack credibility.

Firms that announce open-market share repurchase programs are not obligated to follow through in the actual acquisition of shares. In fact, we find that the majority of firms fail to acquire the target number of shares specified at announcement and many firms fail to repurchase any shares at all. Therefore, the announcement of a share repurchase program has a degree of uncertainty regarding the announcing firms credibility. This study examines the possibility that market participants evaluate the credibility of a firms share repurchase announcement based on the firms previous share repurchase history. We examine 1,507 share repurchase programs for firms listed on the Toronto Stock Exchange (TSX) from 1995 to 2005 and find that firms that have completed a higher proportion of previous share repurchase programs experience larger abnormal returns on the announcement of subsequent repurchase programs. Therefore, we conclude that the market reacts more favorably to the share repurchase announcements of credible firms compared to firms that lack credibility.

none

The objective of my two essays together is to examine whether the trades made by the insiders prior to open market repurchase (OMR) announcements contain information that can be used to identify the repurchases that are motivated by undervaluation. The existing literature on shares repurchases suggests that while undervaluation has been a dominant motive behind repurchases for past few decades, identifying these undervalued firms still remains a challenge. The book-to-market ratio is commonly used as a proxy for mispricing; however, its ability to identify undervalued repurchasing firms has recently come into doubt (Chan et al., 2004). Instead, I propose using proxies based on insider trading to identify the undervalued repurchasing firms.In the first essay, I document a relation between insider trading and both the short- and long-run stock returns of open market repurchasing firms. My findings suggest that the personal trades made by insiders prior to the OMR announcements contain information that can be used to identify undervalued repurchasing firms. I use various measures of insider trading and show that firms with high (low) insider buying (selling) prior to repurchase announcements earn abnormal stock returns in both the short- and long-run. I also find a positive (negative) relation between insider buying (selling) and the actual repurchasing activity of the firms.In my second essay, I further test whether the trades made by insiders prior to OMR announcements contain information that can be used to identify the repurchases that are motivated by undervaluation by examining the post-announcement operating performance. I find a relation between insider trading and the post-announcement operating performance for the OMR firms that is consistent with the hypothesis that insiders' trades prior to OMR announcements are informative. Specifically, I find that firms with high insider buying prior to the OMR announcements outperform their corresponding control firms, whereas, firms with low insider buying do not. In addition, I test for a relation between insider trading and (a) the accruals management around OMR announcements, and (b) the market reaction to the earnings announcements made by the OMR firms. I find a weak evidence of insiders timing their trades along with accruals management. However, the market reaction to earnings announcements made by the OMR firms does not seem to vary with level of insider trading. Overall, the evidence is consistent with insiders of repurchasing firms knowing when their stocks are undervalued and they timing both their personal and firm level trades accordingly.

以往重複事件分析法主要用於醫學與科學領域，近來學者逐漸將其應用至經濟、商學、社會科學等領域，本篇論文採用重複事件分析法，分析S&P 500公司股票回購的行為，回顧過去學者對股票回購之研究，我們檢視公司執行股票回購的三大原因，根據我們的實證結果發現公司可能會以股票回購作為影響公司資本結構的工具，再者亦可能用以減低剩餘資金，然而，本篇論文的實證結果較不支持訊號發射理論。 / In this study, we apply Cox proportional hazard model in recurrent event analysis, which usually used in medical and science studies, to analyze the determinants of the stock repurchase events of S&P 500 companies. We investigate three main incentives that companies conduct stock repurchase. The empirical results show that companies employ repurchase as a technique to alter capital structure. In addition, companies conduct stock repurchase to distribute excess capital. In contrast, there are little evidences to support signaling undervaluation.

This thesis adopts an option approach to examine the stock price reaction to the stock repurchase announcements for both Exchange-listed and Over-the-Counter-listed companies in Taiwan from August 2000 to June 2009. We modify Ikenberry and Vermaelen's (1996) information-asymmetry-based exchange option hypothesis further into a call option hypothesis to accommodate the unique practice in the Taiwanese stock repurchase program. In addition, we conduct robustness tests by including the variables for both information signaling and free cash flow hypotheses which are supported by prior studies. First, we find positive abnormal returns around announcement day, which is similar to previous study. Second, our cross-sectional results support our call option hypothesis, which predicts that the positive abnormal return is positively related to risk-free interest rate, time to maturity and target buyback share fraction. And the abnormal return is negative to the size and market-to-book value of the announcing firm, which are consistent with the signaling hypothesis. However, we do not find any strong evidence for the free cash flow hypothesis.

We reexamine the stock price drifts following open-market stock repurchase announcements by differentiating actual repurchases from repurchase announcements and by controlling for the repurchasing firms' earnings improvement in the announcement year relative to the prior year. Our results show that only firms that actually repurchase their shares exhibit a positive post-announcement drift. More importantly, we find that these repurchasing firms have the same post-announcement drift as their matching firms that have similar size and earnings performance but do not repurchase. Further analysis indicates that the post-repurchase announcement drift is not a distinct anomaly but the well-documented post-earnings announcement drift in disguise. In addition, previous studies suggest that the market perceives IPOs as bad news (i.e., competitive threats) to existing firms in the same industry. At the same time, the market has a tendency to be overly optimistic about IPO prospects, especially during hot IPO markets. Thus, the negative industry rival reaction could be the result of investors' over-optimism toward the IPOs' growth prospects and underestimation of the competitive positions of industry rivals. Our findings show that rival firms use repurchases as a means to signal their firm quality, as well as to correct the market's overreaction to the bad news. These IPO-induced repurchases are stronger when the rival firms are in a concentrated industry and experienced poor stock performance in the previous year.

鑑於我國證券交易市場受非經濟因素影響致股價下跌之情形時而有之，證券主管機關一財政部證券暨期貨管理委員會為健全證券市場之發展，自民國八十五年七月起即積極研議建立庫藏股票制度，直至民國入十九年六月三十日經立法院三讀通過包括證券交易法第二十八條之二有關庫藏股等部分條文修正案，並於同年七月十九日經總統公布後，於同年八月七日訂定發布「上市上櫃公司買回本公司股份辦法」後正式實施。 庫藏股制度之實施，係為一種穩定市場的調節機制，為避免上市、上櫃公司因非財務或業務因素，導致公司股價不合理下跌，而影響公司信用、損及股東權益，於必要時由公司買回自己的股份，其對於企業延攬人才、認股權憑證等金融商品之發行及維護證券市場之安定，有積極之功能與效用。 自八十九年八月十日廣豐實業股份有限公司申報買回股份開始，截至九十年十一月底止，有三○九家上市、櫃公司施行庫藏股制度，目的為轉讓股份予員工、股權轉換或維護公司信用及股東權益而買回其股份。惟我國實施庫藏股制度將近二年，其成效如何，所帶來的經濟效果是否如主管當局所預期，公司所承擔的經營風險又是如何？諸此，乃是本研究的重點。 本研究係以八十九年八月至九十年九月底止已施行庫藏股制度之上市公司為研究對象，透過事件研究法檢驗異常報酬的方式來評估庫藏股制度的宣示效果外，並以CAPM（資本資產訂價模式），觀察公司實施庫藏股前後市場風險（β）變化；另利用無母數統計方法，就上市公司之關係企業交叉持股情況與買回庫藏股作關聯性分析，檢視交叉持股與庫藏股施行之關係。 研究結果如下： 一、公司宣告實施庫藏股前，其股價通常有異常下跌的情形，宣告前三十天至宣告前一日的累積異常報酬高達-11.80％，宣告實施庫藏股後，累積異常報酬逐漸止跌回升，其中以宣告當日至宣告後第三日的異常報酬最為明顯，宣告後三十日累積異常報酬回升至-1.93％，顯示公司實施庫藏股確實存在著穩定股價的效果。 二、公司實施庫藏股後的市場風險月，較宣告前的市場風險心顯著下降，表示就短期而言，公司實施庫藏股後確實能降低該公司證券的市場風險。 三、根據599家上市公司之關係企業持有母公司股份及買回庫藏股資料，利用卡方獨立性檢定，發現交叉持股與實施庫藏股有顯著關聯性；進一步採用Spearman等級相關分析，發現上市公司關係企業持股佔母公司已發行股份總數比例變動情形，與買回公司股份佔其已發行股份總數比例亦有顯著之關聯，呈同向變動，亦即交叉持股的情況未因庫藏股之實施而有所減少。 關鍵字：庫藏股、股票買回、交叉持股 / Seeing that sometimes our stock markets are disturbed by non-economic factors makes the price of stock come down. The Securities and Futures Commission (SFC) has been committed to developing a sound stock market. It began to consider establishing the treasury stock system since July 1996. The amendment of The Securities Law, promulgated on July 19, 2000, includes the treasury stock system. SFC announced the“Guidelines for Buying Back Company shares by TSE-listed and OTC-listed Companies”on August 7,2000. The treasury stock system is an adjustment mechanism of stable market, in order to avoid the unreasonable falling in stock price of TSE-listed and OTC- listed Companies by non-financial or financial factors, influence company credit and shareholders' equity. The company can buy back shares when it is necessary. It is positive that the company invites qualified personnel, the warrants are issued and the stability of the stock market is maintained. Since Kwong Fong Industries Corporation started to declare buying back shares on August 10, 2000. By the end of Nov. 2001, a total of 3 09 TSE-listed and OTC-listed companies carried out the treasury stock system. These companies buy back shares for the purpose of transferring to employee, conversion of stock equity, maintaining company trust and stockholders' equity. We have carried out the treasury stock system for two years. How are effects of the treasury stock system? Did it come up to expectations of SFC? How are risks of these companies operating? Such these topics are focus of this research. These TSE-listed companies of buying back company shares from August 2000 to September 2001 are objects of this study. An event study methodology is used to examine the excess returns to evaluate the announcement effects of treasury stock. By CAPM, it can compare the changes on market risk before and after these companies carried out the treasury stock system. Nonparametric method is used to analyze the relationship between the cross holding and the stock repurchase. The results of this study are as follows: 1.The stock price is often descending before the announcement on buying back company shares, the accumulative abnormal returns reach -11.080% from 30 days to I day before stock-repurchase announcement, but the accumulative abnormal returns are increasing gradually after stock-repurchase announcement. The abnormal returns have significantly from the day of announcement to 3 days after the announcement. The accumulative abnormal returns reach -1.93% on 30 days after stock-repurchase announcement. So, it exists the stock price stability effect on carrying out the treasury stock system. 2.The market risk after company buying back shares is lower significantly. In the short term, the company using the treasury stock system can reduce market risk. 3.There are significant relation between Cross-holding and stock-repurchase. Furthermore, the ratio of parent company's shares held by its subsidiary company has positive correlation with that of parent company buy back shares of its own. Key words: Treasury stock ; Stock repurchase ; Cross holding