為實施最低稅負制，我國特別制定「所得基本稅額條例」，於民國95年開始施行，其政策目的為提升租稅公平，確保國家稅收，使有能力納稅者，對國家財政均有基本的貢獻。本研究探討的問題為上市（櫃）公司有效稅率以及上市（櫃）公司之企業特性，是否影響其加徵最低稅負之機率及加徵最低稅負之金額。 　　本研究實證結果顯示有效稅率較低者，則其加徵最低稅負之機率及加徵稅額愈大，顯示最低稅負制對於有效稅率偏低之上市（櫃）公司，確實可合理提高其租稅負擔。企業規模愈大其加徵最低稅負之機率及加徵稅額愈大。然而，並未有實證結果顯示企業之獲利能力及所屬產業為電子業者，與其加徵最低稅負之機率及加徵稅額為正向之關係。證券交易所得、研發支出比例與加徵最低稅負之機率及加徵稅額為正向之關係。在最低稅負制實施初期應即可減緩對於證券交易所得免稅及研發支出租稅優惠等所帶來稅負不公之現象。 / The Income Basic Tax Act (IBTA) imposes a minimum tax similar to an Alternative Minimum Tax (AMT) and collects a certain amount of minimum tax payment from high-income individuals and enterprises that used to pay disproportionately low taxes or even none. Corporate and individual AMT were first put into the R.O.C. Tax Code in 2006. 　　This study examines the relationship between effective tax rate and AMT tax burden of listed firms. Also, the study investigates the relationship between firm characteristics and AMT tax burden of the listed firms. The empirical results of the study indicate that effective tax rates are negatively related to AMT burden and that firm size is positively related to AMT burden. In addition, tax-exempt capital gains on securities and tax incentive for R&D exependitures, the major elements of the increase in tax liability under AMT, are positively related to AMT tax burden. 　　The results of this study suggest that by raising the tax burden of companies pay lower effective tax rates, the implementation of AMT has yield a positive effect on the fairness of the tax system.

民國95年開始實施之最低稅負制，是我國繼兩稅合一後，另一重大所得稅制改革，而以往部分文獻在討論營利事業最低稅負制時，均前提假設在維持政府稅收不變之情形下，最低稅負制為取消未分配盈餘加徵稅制的替代方案之一。然而可能的替代方案不應僅有兩三類，更何況適用兩制之企業是否屬於相同的產業，亦有待釐清。 本研究以民國93至95年所有上市公司為研究對象，透過公開資訊觀測站與台灣經濟新報資料庫（TEJ）所提供之公司財務報表資料，模擬推算出各上市公司在實施最低稅負制下，可能須補繳之最低稅負金額，再與公司負擔之未分配盈餘加徵10％稅額作比較，以瞭解在實施未分配加徵稅制與最低稅負制下，對於上市公司之稅負有何影響，以及是否對相同產業有加重稅負之現象。 根據實證研究結果可知，在同時實施未分配盈餘加徵稅制與最低稅負制下，電子工業為負擔最多未分配盈餘稅負與最低稅負之產業，顯示出對特定產業明顯有加重稅負之情形。以及公司獲利能力較佳、規模較大之營利事業亦須負擔較多的未分配盈餘加徵稅額與最低稅負金額。然而實施未分配盈餘加徵稅制主要是為了彌補稅制缺陷；最低稅負制則是為了解決租稅不公平性的問題。且未分配盈餘加徵規定之適用對象為全體營利事業，而最低稅負制之實施對象為少數適用租稅優惠之營利事業。因此，本研究認為最低稅負制不應作為取消未分配盈餘加徵稅制之替代方案。

本研究主要目的，即在以迴歸模型量化依最低稅負制納稅企業的投資行為，比較我國依最低稅負制納稅及依一般稅率納稅企業的國內投資金額，進而分析政府在實施新稅制下課徵稅收，是否影響我國企業的投資意願，了解不同產業類別受最低稅負制之衝擊或影響程度。擬以Menzel(1990)研究所採用的模型及假設，以本國國內外企業為研究對象，結果顯示企業的資產或所得兩變數對國內投資有正向影響。其次探討最低稅負制對於企業投資所減少的幅度：於本研究假設下，並無顯著證據證明新稅制會使企業減少其國內投資金額；換言之，最低稅負制政策並不至於顯著影響企業的投資決策。 最後針對企業、政府等部門提出建議供參。首先，針對企業部門而言，無論是國內企業或是跨國投資企業，其對國內、外之投資都不因是否依新稅制納稅而有顯著的變化，表示新稅制並不會造成扭曲國內企業與跨國投資企業於國內投資之決策，當然也不至於影響國內資本的累積，企業於作投資決策的同時，毋須擔心適用不同的稅制是否產生不同的租稅負擔。而對政府部門而言，就本研究所設定的假設條件下，亦證實了最低稅負制不至於影響我國企業的投資決策，對國內投資的影響不大，此結果無疑為近年來國內所推動的新稅制，奠定了強而有力的基礎，政府藉由推行最低稅負制作為進行財政改革的短期方案之一，除可發揮一稅制所應具備的所得重分配效果，使各產業間租稅負擔更趨公平化，未來對於財政部所期望的「配合行政院財政改革方案之中、長期措施，逐步推動實施稅制改革方案，以期達成妥善調整稅制結構、追求稅收穩定與適足、租稅公平與效率」等目標而言，將有莫大的助益。 / The purpose of this dissertation is to document and quantify the impact of investment incentives under the alternative minimum tax (AMT) on domestic corporations’ investment decisions. On the one hand, this research addresses whether new domestic capital investment by AMT corporations is less than that of regular tax corporation; on the other hand, it also examines whether multinational AMT corporations invest less in Taiwan than domestic AMT corporations. With the same models and assumptions used by Mezel’s research method, I find that multinational AMT corporations, compared with multinational corporations paying with regular tax policy, do not exhibit significantly higher levels of foreign investment. This consequence shows that the AMT rules do not significantly influence multinational corporations either to invest less in Taiwan or to substitute foreign for domestic investment. In other words, there is weak evidence that the AMT rules do significantly influence the domestic corporations’investment decisions. The last part of my essay provides some suggestions for the domestic corporations and the relative departments of the government at the same time. First, since the results of this study indicate that, in general, the AMT rules do not affect the investment dicisions of AMT corporations by causing them to invest less in Taiwan, the domestic corporations are not worried about that new tax policy distorts the investment decisions. Further, the results do not indicate any evidence that corporations shift their investments overseas at the expense of domestic ones, which means the incentives described in the analytical research do not exist. Therefore, for the government, policymakers should carefully consider whether any new tax reforms are necessary, such as AMT rules, for pursuing the goals of taxiation stability and adquency in the long run.

本研究主要在探討最低稅負制實施後，對我國上市櫃電子業稅負影響情況為何。不同於以往文獻以營利事業所得稅申報資料來進行模擬分析，本研究以財務報表之所得稅附註資料進行模擬設算。不用營利事業所得稅申報資料進行模擬乃因該資料取得不易，並非一般投資大眾所能獲取之資料，本研究乃嘗試使用財務報表之所得稅附註資料進行模擬設算，希望能模擬出最低稅負制之實施對電子業之影響情形。此外，本研究利用模擬設算之基本稅額與一般所得稅額之差額當成依變數，建立一條迴歸式，希望能從中發現最低稅負制實施後，受影響之公司具有哪些特性，以供投資人在選擇投資標的時有所參考。 本研究經過篩選後，對我國上市櫃電子業的其中206家公司進行民國93年及94年的模擬設算。其設算結果為平均每年每家公司會增加1,000多萬元的稅負，而約有3成的公司將會受到影響。實證結果亦證實最低稅負制實施後，對於我國上市櫃電子業確實有明顯的租稅負擔。迴歸結果則發現，對於股東可扣抵稅額愈小、研發費用愈高、獲利能力愈佳及公司規模愈大之公司會有較明顯的租稅負擔。此種情形是否對這些公司之競爭力造成不利影響，非常值得關心。此外，電子業競爭相當激烈，必須投入相當多的研究發展費用與相關的重大投資，而經本研究結果也證實，研發費用愈高的公司，在最低稅負實施後，將補繳愈多的稅額，未來公司在從事這些支出時，應更加審慎評估。 / This study investigates the effects that the implementation of Alternative Minimum Tax (AMT) has on our electronic industries publicly listed in Taiwan Stock Exchange. Past studies often utilized the income tax reported by profit-seeking enterprises; nevertheless, these data are not accessible to the public. In view of this, the current study attempts to simulate calculating the appendix of income tax in financial statements, with an aim to simulating the impacts that implementation of AMT exerts on the electronic industries. Furthermore, as the difference between the simulated Basic tax and Regular tax is the dependent variable, established is a regression model, with which the characteristics of the companies influenced by the implementation of AMT can be identified, so that investors can refer to when they choose investing targets. After the sampling, the simulating calculation on two years, i.e. 2004 and 2005 has been conducted among 206 companies among the publicly listed electronic industries. The results of calculation demonstrate that each company would have more than ten million taxes each year and approximately thirty percent of the firms will be influenced by the implementation of AMT. Empirical results also confirm that there will be significant tax burdens after AMT takes effect. Moreover, the outcomes of regression analysis indicate that more salient tax burdens will be imposed upon the firms with larger size, smaller shareholder deductible tax, higher research funds, and more profitability.