In this paper, optimal TAX rates for real and legal entity INCOME TAXes have been estimated. Optimal TAXation means optimal maximization of total utility functions of entities with regard to the budget constraint and a constraint wherein the entities make their choices of labor supply taking into consideration the relationship between labor and INCOME. The foundation of our estimation has been Diamond’s model (1998) which is itself an extended form of Diamond and Myrrless’s model (1971). This model is, in its turn, an adaptation of Saez’s model, an important optimal TAXation model. The statistic population being used for the calculation includes real entities in Tehran and legal entities in Tehran and Kermanshah cities. In order to cover the fairness of INCOME distribution, the statistical data has been classified in terms of INCOME deciles, and Gini coefficient was calculated as an indicator of INCOME distribution variance. Then, an appropriate model which is assumed to have the best impact on the decrease of the Gini coefficient has been selected. Finally, through the application of the selected model and taking into account different levels labor force elasticity (for real entities) and services supply elasticity (for legal entities), the optimal TAX rates have been calculated. The results obtained indicate that in the Iranian TAX system, the application of new rates would lead to a better distribution of INCOME as well as an increase of 150% in the government TAX revenues. Moreover, the calculated rates are able to be interpreted on the basis of an extended formulation of Laffer’s curve.

One of the most important considerations for designing a proper TAX system is to not disturb economic system as much as possible. This study compares the economic effects of consumption and CORPORATE INCOME TAXations, using a Computable General Equilibrium (CGE) model. The model is calibrated using the Social Accounting Matrix and the Input-Output table of Iran’s economy in 2011. First, we assess a scenario in which consumption TAX has been raised gradually up to 100% of its base amount, along with a proportional decrease in CORPORATE INCOME TAX. Overall, the government TAX revenue is held fixed. Here, the intermediary goods become expensive, causing the production to decline. Moreover, we observe a rise in savings and investment, however, this has no effect on production since savings are not entering the production process in short run. The second scenario is a dynamic one, in which an increase in consumption TAX is compensating a decrease in CORPORATE INCOME TAX, holding government budget fixed. As in the static model results, we observe a rise in intermediary goods prices, a reduction in the production of the first period, but also an increase in future production which is construed as the result of an increase in savings and investment streaming into the production process in long run.

Estimating TAX capacity of a region or of the whole country provides the information needed for responding to financial and executive problems resulted from the implementation of economic policies. The present study aims at estimating TAX capacities of the two TAX categories, “business and profession INCOME TAX” and “CORPORATE INCOME TAX” in the Iranian provinces through making use of the data of some effective variables. To this end, we have explored the variables involved in TAX revenues of the provinces, and by using data of 28 different provinces within the time span 1379-1385 (2000-2006), we have resorted to SFA method to estimate the efficiency of each TAX category in question in any of the Iranian provinces. According to the findings obtained, as for the business and profession INCOME TAX, the average TAX efficiency of developed provinces (excluding Tehran Province) for the period in question has been 72.3% while it has been 66.5% in less developed provinces. And as for CORPORATE TAX INCOME, the average TAX efficiency of developed provinces (excluding Tehran Province) has been 47.8% while it has been 72.4% in less developed provinces. The present research has calculated the “TAX inefficiency” of each province as the gap between the potential and realized legal capacities. As for TAX effort indices, the results show that over time, the average TAX effort has decreased for business and profession INCOME TAX but it has increased for CORPORATE INCOME TAX.

Effective TAX rate is one of the most important TAX efficiency criteria in TAX literature. Moreover, TAX system efficiency is usually measured by bilateral comparison between administrative costs and effective TAX rate. By examination and estimation of effective TAX rate, TAX authorities are able to increase TAX justice and investigate TAX burden on TAXpayers. Effective TAX rate could be an instrument to direct capitals, as well as its wide using in policy-making and economic decisions. In present paper an attempt is made to estimate effective TAX rate in business and CORPORATE INCOME TAX. The results show that effective CORPORATE TAX rate had an increasing trend from 6.08 to 11.59 during 2001 to 2008 while effective business TAX rate has been decreased by 2.1 to 1.3 between 2001 and 2007.

This paper is an attempt to analyze the impact of INCOME TAXes and market capitalization on fixed investment (investment in tangible assets) by manufacturing companies listed on KSE. This paper basically examines that how CORPORATE INCOME TAXes affect fixed investment by reducing cash flow available for a firm to invest and how the firm size in the lights of market capitalization affects fixed investment by manufacturing companies. As market capitalization leads to development and due to this development investment opportunities increase. Estimation is based on pooled regression by employing fixed effect model. The results of the study show that there is positive impact of market capitalization and fixed investment while there is negative impact of INCOME TAXes and fixed investment by manufacturing companies.

Objective: This article seeks to extend the concept of TAX elasticity to CORPORATE TAX sensitivity. This issue is interpreted as CORPORATE TAX stickiness (changes in the CORPORATE INCOME TAX to changes in the net INCOME). In other words, in the sense of TAX stickiness, the CORPORATE INCOME is analyzed instead of GDP, and the CORPORATE INCOME TAX instead of government TAX revenues. Theoretically, it is unlikely that the company's TAX will always increase. In other words, when the company's INCOME decreases, so does the TAX. But given the stickiness of the TAX, the pace of change between the two will be asymmetric. TAX policy is one of the most important factors affecting macroeconomic variables. Studying changes in TAX revenue in response to variations in GDP is the key concept in this area. Based on the above argument, the main purpose of this study is to examine TAX elasticity at a micro level (called TAX stickiness). The rate of change in CORPORATE INCOME TAX is compared to changes in CORPORATE INCOME (profit). TAX stickiness exists when the rate of TAX reduction is less than the rate of profit reduction. Method: In this study, data were collected from a sample of 284 companies listed on the Tehran Stock Exchange, TSE, in the period 2012-2019. Data were analyzed using a regression model. Result: The results showed that there is no TAX stickiness in the studied companies. Also, the effects of the variables of economic growth and capital intensity are not significant. However, financial leverage can decrease TAX stickiness. In the third and fourth hypotheses, the effects of economic growth and capital intensity on TAX stickiness were tested. It is argued that in the conditions of economic growth and high capital intensity, the level of investment of the companies increases, and the TAX revenue from capital raises. Given that there is no capital TAX in the TAX structure, the lack of effects of economic growth and capital intensity on TAX stickiness in the companies under study can be justified. Conclusion: The reasons for the lack of effects of economic growth and capital intensity on TAX stickiness can be attributed to government TAX policies, reduction of reliance on CORPORATE INCOME TAX in the studied years, and low attention to the capital TAXation in the TAX structure. On the other hand, TAX stickiness can be attributed to the expertise of the TSE companies in TAX planning compared to the non-TSE companies. In short, given the importance of TAX revenue in the current condition of sanctions (reducing economic growth rates), it is desirable to allocate appropriate weight to capital TAX in the state TAX structure. The positive effects of revealing the uncertain TAX situation and the motivation of managers' reward on TAX avoidance, and the prominence of these features in the TSE companies compared to the non-TSE companies can be interpreted as non-stickiness of TAXes. Also, in terms of the positive effects on TAX avoidance, the lack of TAX stickiness in the TSE companies can be attributed to the overconfidence of the managers of these companies. All these features can be the reasons for the non-sticking of INCOME TAX to the companies under study.

Abstract According to Article 198 of the Direct TAXes Act, in commercial companies, company managers, collectively or individually, are jointly and severally responsible to the company for paying the company's INCOME TAX that has been final during their management. Based on the principle of the independence of the legal personality of the managers from the company, the debt of the company can only be claimed from the company itself, as a result, claiming the company's TAX debt from the managers is against the aforementioned legal principle. On the other hand, according to the principle of personal TAX responsibility, TAX can only be claimed from the TAXpayer, i.e. the company. Article 198 is written in such a way that the joint and several liability of directors is general, absolute, and as a result includes all members of the board of directors, including the signatory directors and others, as well as those who are faulty or not faulty of non-payment of TAXes. Since the ruling on the personal responsibility of managers for company TAX is against the principles governing CORPORATE law, obligation law, and TAX law, as well as restricting the individual rights of board members and the CEO of the company, the legal analysis of this issue in the framework of the concepts and principles of the legal system in related fields can reveal new angles about the basics of managers' responsibility for CORPORATE TAXes and appropriate legal policy in this matter. The issue that can be raised is whether the provision of Article 198 of the Act is justified from a legal point of view or not. Is it justifiable to impose personal responsibility on managers for company TAXes, based on the principles of TAX law, obligation law,CORPORATE law, and other related legal fields? What is the ideal legal system for the legal regulation of managers' responsibility for CORPORATE TAXes? The theoretical framework of the research is based on several principles and accepted in related legal fields, including the principle of independence of the legal personality of managers from the company, the principle of individuality of TAX, the principle of individuality of responsibility, the principle of the ability to pay TAXes, the principle of TAX justice, the principle of ease of TAX collection, The principle of guaranteeing public rights, the moral principle of responsibility, and other relevant principles, and a balance between these principles are organized. The sources of this research are derived from legal principles and principles in related fields, fundamental principles, and the subject of legal consensus, including justice and individual rights, relevant laws and regulations, as well as relevant and useful findings in comparative law. The research method in this article is comparative and the validation of Article 198 of the Act is analyzed, reasoned, and deduced based on the criteria derived from certain legal principles in related legal fields including TAX law, CORPORATE law, public law, and civil liability law. This article tries to prove the hypothesis with legal analysis that the imposition of such responsibility is unjustified and incompatible with the foundations, principles, and integrity of the legal system. Based on the research conducted in this article, the joint and several liability of managers for company TAX, which is very strict against managers to facilitate TAX collection and deal with any possibility of TAX abuse, regardless of the manager's role, authority, and ability to not pay TAX. The imposed TAX is contrary to the desired legal and TAX system and is a clear violation of individual rights and the extensive and unjustified use of public law tools. The main objection is that Article 198 sacrifices the role of fairness, justice, individual rights and freedoms, the moral aspects of the legal system, and the integrity of the legal system without providing the necessary justifications and bases for the expediency of providing TAX revenue for the government. From the point of view of this research, the ideal legal system for defining the responsibility of managers for CORPORATE TAXes is the civil liability system, which uses legal and acceptable elements and takes into account effective factors such as the manager's obligation to pay the company TAX, the manager's fault in paying the TAX, The role and authority of the manager in paying TAXes, the presence or absence of sufficient resources in the company to pay TAXes and other responsibility factors, to establish a fair and efficient system.

This study inves tigates the effects of TAX avoidance on TAX risk using a conceptual and statistical modeling of TAX risk measuring, based on uncertainty indicator. The sample consists of 114 firms in the period from 2009 to 2016. TAX avoidance is measured by the effective TAX rate (ETR). Also TAX risk is measured using the EGARCH model and defined as the instability of TAX status over time. The research findings show that there is a significant negative relation between effective TAX rate and instability of the TAX status, which means that firms with lower effective TAX rate have instability of TAX status over time. On the other hand, findings indicate an increase in TAX difference in event of effective TAX rate decreases. According to findings, one of the consequences of TAX avoidance is increases of TAX risk. The findings provide new evidence about the consequences of CORPORATE TAX avoidance. These findings can be used to assess the TAX risk of firms based on their effective TAX rate. Also the findings suggest investors and managements to consider the consequences of CORPORATE TAX decreases.

In this paper, to evaluate INCOME and distributional effects of Personal INCOME TAX, a hypothetical society is simulated.12 INCOME sources are defined that each member of society can earn INCOME from one INCOME source or more. Then, using FORTRAN programming, the government's TAX INCOME, INCOME distribution and average TAX rate are calculated, assuming five alternative Scenarios: 0. Base scenario: TAXing personal INCOME at source according to "Direct INCOME TAXes Act"; 1. TAXing the sum of INCOMEs each individual person earns from different businesses he or she owns and exempt his / her business INCOME once; 2. TAXing the sum of INCOMEs each person earns from non-exempt sources and exempt his / her business INCOME once; 3. TAXing the sum of INCOMEs each person earns from exempt and non-exempt sources and exempt his / her business INCOME once; 4. qualifying third scenario by accepting a 1 billion Rials as exemption. Results of simulation indicate that the government's INCOME and INCOME equality is maximized in 3rd scenario.