股票購回宣告可信度驗證

An Examination on the Credibility of Share Repurchase Announcements

賴瑋琪(Wei-Chi Lai)

指導教授 ： 楊淑玲

國立臺中科技大學/資訊與流通學院/流通管理系碩士班/碩士(2015年)

https://doi.org/10.6826/NUTC.2015.00068

摘要

本研究旨在透過股票購回宣告前盈餘管理與宣告後執行目的一致性的觀察，探討2001年10月至2014年9月間，我國上市櫃公司宣告股票購回企業之內部人是否存有自利之行為。在不考慮宣告前後購回目的是否具有一致性的狀況下，宣告前公司盈餘管理的高低，對宣告後股價長短期績效的表現，與宣告期間內部人持股變動均無顯著影響，內部人並未存有自利行為。然在考量事前宣告與事後實際執行目的的不一致後發現，多數企業事前宣告「轉讓員工」目的，事後卻行「買回註銷」之實，此目的不具可信度的宣告事件，不僅宣告前有顯著較高的股價壓力與盈餘操弄，且內部人顯著增加持股，而在宣告後則有顯著較高的執行率與較差的股價長期績效。此結果似乎說明了，內部人可能藉由事後實際執行買回註銷之行為，以達短期提高每股盈餘之自利目的。

關鍵字

盈餘管理 ； 股價壓力 ； 股價績效 ； 內部交易

並列摘要

This study examined whether the self-interest behavior of insiders exist as firms announce false share repurchase. I observed earning management prior to announcement and the credibility of share repurchase purpose from October 2010 through September 2014. For any ex ante announced purpose events, this study found abnormal accrual did not has a substantial effect on the performance of stock prices following the announcement or change in insiders’ ownership. There are not self-interest behaviors for insiders. However, when I observed actual share repurchases following announcements further and found that a lot of firms ex post executed “buying back and canceled” behavior instead of ex ante “transfer employees” announcement. Those incredible events not only bore higher ex ante stock price pressure and earning management and insiders’ ownership increasing prior to the announcement but also have higher execute ratio and poor long-term stock performance following announcement. These results seemed to indicate that insider probably benefited by ex post actually “buying back and canceled” action to raise earning per share.

並列關鍵字

Abnormal Accrual ； Stock Pressure ； Stock Price Performance ； Insider Transactions

參考文獻

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