兩稅合一前後投資人實際參與除權除息之研究

Abstract

我國自民國八十七年一月一日起正式實施兩稅合一制度，兩稅合一制度實施之後，在公司階段所繳納的營所稅可以在個人階段的綜所稅中扣抵，可以說營所稅成了綜所稅的預繳稅款。當個人綜所稅的適用稅率大於公司的營所稅稅率時，股東需要補繳稅款給國庫；相反情形下，股東適用稅率較低時則可以獲得退稅。兩稅合一制度不僅消除了重複課稅的問題，也減輕了投資人的租稅負擔，創造出更有利的投資環境。 本文主要討論兩稅合一後，大股東實質稅率降低，小股東有退稅誘因下，其實際參與除權息之行為是否改變。本文之研究問題包括： (一)兩稅合一後，大股東是否有明顯棄權規避稅負之行為，而小股東是否因退稅之誘因而增加除權息之誘因 (二)兩稅合一前後，大股東及小股東對於電子業及非電子業參與除權息之意願是否明顯不同 (三)股東會至除權息前，大股東是否有明顯棄權息效應 研究顯示，大股東在兩稅合一前後，持股比例並無顯著變化，而小股東持股明顯增加，顯示小股東確有因退稅誘因參加除權息。 另以過去論文研究結果，股票在除權息前後有異常交易量，而「先買後賣」會有超額報酬，若以本研究推論，此部份異常交易量應來自於中間股東之高稅率者之賣出，而低稅率之小股東買進。大股東基於長期經營權控制及實質稅率降低，持股並沒有明顯變化。 在電子業及非電子業之驗證結果，無論兩稅合一後一年或二年，小股東參與除權之持股比例均明顯增加，顯示小股東對可扣抵稅額退稅之誘因，無論電子及非電子均有意願參與除權息。而大股東方面，則在兩稅合一後一年或二年，對非電子業有明顯參與除權息之意願，應可解釋實質稅率降低後提高除權意願。但在兩稅合一後二年，電子業大股東參與除權比例明顯降低，可能係電子業之可扣抵稅額較低，因此相對意願較低。 在大股東於除權息前是否有棄權之研究方面，以86-93年度之持股資料檢定，僅89及92年度大股東持股有明顯下降，其餘各年度並無明顯變化，顯示大股東在此段期間之棄權效應並不明顯，除權息前異常交易量應來自於中間股東。

Before the change on the first of January 1998, dividend income was double taxed for both the personal income tax and corporate income tax in Taiwan. A new income tax law became effective which began to take the corporate income tax as tax credit when shareholders file their personal income tax. Under the new income tax law, corporate income tax at 25% flat rate becomes tax credit of 33.33% deductible for shareholders’ income tax. According to Taiwanese taxation, however, companies in the tech sector normally receive tax incentive and have less corporate income tax than normal 25%. This study empirically examined whether major shareholders (holding 1000 thousand shares and more) behave differently from minor shareholders (holding 50 thousand shares and less) under the new tax law on the ex-dividend day. The purpose of this study is to discuss the following questions: i) Under the new taxation, will major shareholders sell shares before ex-dividend day and buy back shares afterwards? Will minor shareholders be motivated to buy shares before ex-dividend day to enjoy tax return? ii) Will the corporate tax subsidy in the tech sector and non-tech sector change the behavior of major shareholders as well as minor shareholders? iii) The period from the annual general meeting to ex-dividend, will major shareholders sell out their shareholding to avoid income tax? This study sampled listed companies and empirically examined their shareholding data in the period between 1997 and 2004. Before and after the new tax law, major shareholders have not shown any significance in their shareholding on ex-dividend day. On the other hand, motivated by tax incentive minor shareholders have significantly increased shareholding. Trading volume has increased before ex-dividend day, because minor shareholders with low income tax normally are encouraged to receive tax return by investing shares. Major shareholders in the non-tech sector have shown the increase of holding on ex-dividend day, since they enjoy higher disposal income under the new tax system. Major shareholders in the tech sector have shown a negative attitude toward the participation of dividend payout.