K. Sreedhar Rao, CJ (Acting) 1. The writ petitioners are the industrial units employed in manufacturing b of coal into coke. The State of Assam issued the Industrial Policy, dated 1.10.2008, which gave VAT concessions to the industries established and production commenced on or after 1.10.2008 for a period of 7 years. The petitioners had submitted applications to the Department of Industries to avail the tax benefits. The eligibility certificates were yet to be issued c after scrutiny by the Industrial Department. During the pendency of the request for grant of eligibility certificate, rule 57A was incorporated in Assam Value Added Tax Rules, 2005. Rule 57A reads as under : "57A. Activities which are not to be treated as manufacture. -- The following activities shall not be treated as manufacture for the purposes of the Act d retrospectively with effect from 1st October, 2008 namely - (a) sawmill, (b) Tea industry, (c) Galvanization, corrugation of sheet or both, (d) Marble and decorative stone cutting from slabs/sheets and polishing unit, (e) Paper cutting from roll paper, (f) Coal to washed coal, sized coal, (g) Conversion of plain rod to tor rod, (h) Refining and packing of mustard oil, (i) Refining of engine oil, (j) Purification and /or packaging of drinking water, (k) Production of cooked food, sweet meats and namkins, if the investment in plaint and machinery in a unit is less than rupees five crores, (1) Conversion of coal to coke." 2. The petitioners aggrieved by the said amended Rule, have filed this writ petition challenging its application to their units and its validity. Section 2(30) of the Assam Value Added Tax Act, 2003, defines 'manufacture' as follows : "manufacture' means any activity that brings out a change in an article or articles as a result of some process, treatment, labour and results in transformations into a new and different article so understood in commercial parlance having a distinct name, character use, but does not include such activity of manufacture as may be prescribed." 3. Dr. A.K. Saraf, learned senior counsel for the petitioners submitted that as per the definition of 'manufacture', the process of conversion of coal to coke is a manufacturing process. However, the amended provision of section 57A, which came into force w.e.f. 3.11.2009, with retrospective effect, has omitted the process of conversion of coal to coke as a manufacturing process. Dr. A.K. Saraf, learned senior counsel for the petitioners submitted that as per the definition of 'manufacture', the process of conversion of coal to coke is a manufacturing process. However, the amended provision of section 57A, which came into force w.e.f. 3.11.2009, with retrospective effect, has omitted the process of conversion of coal to coke as a manufacturing process. It is argued that as on the date when the unit was established and production was commenced, the process of conversion of coal to coke was a manufacturing process within the definition. However, under the Rules, the definition of 'manufacture' is altered retrospectively. The executive, by its rule making power, cannot alter any provision of the Act under the guise of rule making power, since Rules shall always be subordinate to the provisions of the Act and cannot prevail or override the provisions of the Act. Therefore, the rule 57A(1) is ultra vires. It is further argued that by virtue of the definition of 'manufacture' under the Act, the industrial policy, which extended tax benefit to the industries, which commenced production on or after the date of Industrial Policy, 2008, would get accrued and vested right. The State, by amendment of Rules by way of delegated legislation, cannot take away the vested or the accrued rights on the pretext of exercise of legislative powers. 4. In this regard the observations made in paragraphs 21, 22, 23, 24, 37, 38, 41, 42, 43 and 44 of the decision of the Supreme Court in Mahabir Vegetable Oils (P) Ltd. and Another v. State ofHaryana and Others, (2006) 3 SCC 620 , have been relied upon, which read as follows : "21. Mr. Manjeet Singh, learned counsel appearing on behalf of the State, on the other hand, submitted that: (a) Draft rules having been published by the State by way of a notification dated 3.1.1996 all the prospective entrepreneurs were aware that the said Rules may be amended. (b) There was no reason for the appellants being misled by reason of the existing Rules. (c) As on the date of final notification, the appellants did not commence commercial production, they did not acquire any legal right to obtain any exemption. (d) The State has the requisite jurisdiction to make amendments with retrospective effect. (b) There was no reason for the appellants being misled by reason of the existing Rules. (c) As on the date of final notification, the appellants did not commence commercial production, they did not acquire any legal right to obtain any exemption. (d) The State has the requisite jurisdiction to make amendments with retrospective effect. (e) In any event, the right of the entrepreneurs being not an indefeasible right, the same could be withdrawn before commencement of production. 22. It is not in dispute that when the appellants herein started making investments, rule 28A was operative. Representation indisputably was made in terms of the said Rules. The State, as noticed hereinbefore, made a long-term industrial policy. From time to time it makes changes in the policy keeping in view the situational change. 23. The State intended inter alia to grant incentive to include industrial units by way of waiver and/or deferment of payment of sales tax wherefor rule 28A was made. The sales tax laws enacted by the State, as noticed hereinbefore, contain a provision empowering the State to grant such exemption. 24. The relevant provisions of the Act and the Rules framed thereunder indisputably were made keeping in view the industrial policy of the State. Such industrial policies by way of legislation or otherwise, subject, of course, to the provisions of the statute have been framed by several other States. 37. It is true that the State issued a notification on or about 3.1.1996 expressing its intention to amend the Rules. By reason thereof, however, the State neither stated nor could it expressly state, that the Rules shall stand amended. It is now well-settled principle of law that the draft rules can be invoked only when no rule is operative in the field. Recourse to the draft rules for the purpose of taking a decision in certain matters can also be taken subject to certain conditions -- see Union of India v. V. Ramakrishnan, SCC paras 23 and 24. 38. The promises/representations made by way of a statute, therefore, continued to operate in the field. It may be true that the appellants altered their position only from August 1996 but it has neither been denied nor disputed that during the relevant period, namely, August 1996 to 16.12.1996 not only have they invested huge amounts but also the authorities of the State sanctioned benefits, granted permissions. It may be true that the appellants altered their position only from August 1996 but it has neither been denied nor disputed that during the relevant period, namely, August 1996 to 16.12.1996 not only have they invested huge amounts but also the authorities of the State sanctioned benefits, granted permissions. Parties had also taken other steps which could be taken only for the purpose of setting up of a new industrial unit. An entrepreneur who sets up an industry in a backward area unless otherwise prohibited, is entitled to alter his position pursuant to or in furtherance of the promises or representations made by the State. The State accepted that equity operated in favour of the entrepreneurs by issuing Note 2 to the notification dated 16.12.1996 whereby and whereunder solvent extraction plant was for the first time inserted in Schedule III, i.e., in the negative list. 41. We may at this stage consider the effect of omission of the said note. It is beyond any cavil that a subordinate legislation can be given a retrospective effect and retroactive operation, if any power in this behalf is contained in the main Act. The rule-making power is a species of delegated legislation. A delegatee therefore can make rules only within the four corners thereof. 42. It is a fundamental rule of law that no statute shall be construed to have a retrospective operation unless such a construction appears very clearly in the terms of the Act, or arises by necessary and distinct implication -- see West v. Gwynne. 43. A retrospective effect to an amendment by way of a delegated legislation b could be given, thus, only after coming into force of sub-section (2A) of section 64 of the Act and not prior thereto. 44. By reason of Note 2, certain rights were conferred. Although there lies a distinction between vested rights and accrued rights as by reason of a delegated legislation, a right cannot be taken away. The amendments carried out in 1996 as also the subsequent amendments made prior to 2001, could not, thus, have taken away the rights of the appellant with retrospective effect." 5. The Supreme Court, in paragraph 24 of the decision rendered in Chairman, Railway Board and Others v. C.R. Rangadhamaiah and Others, (1997) " 6 SCC 623, has made the following observations : "24. The Supreme Court, in paragraph 24 of the decision rendered in Chairman, Railway Board and Others v. C.R. Rangadhamaiah and Others, (1997) " 6 SCC 623, has made the following observations : "24. In many of these decisions the expressions "vested rights" or "accrued rights" have been used while striking down the impugned provisions which had been given retrospective operation so as to have an adverse effect in the matter of promotion, seniority, substantive appointment, etc., of the employees. The said expressions have been used in the context of a right flowing under the relevant rule which was sought to be altered with effect from an anterior date and thereby taking away the benefits available under the rule in force at that time. It has been held that such an amendment having retrospective operation which has the effect of taking away a benefit already available to the employee under the existing rule is arbitrary, discriminatory and violative of the rights guaranteed under articles 14 and 16 of the Constitution. We are unable to hold that these decisions are not in consonance with the decisions in Roshan Lai Tandon, B.S. Yadav and Raman Lai Keshav Lai Soni." 6. Per contra, Sri S Saikia, the counsel for the Department relied upon the decision of the Supreme Court in R.C. Tobacco (P.) Ltd. and Another v. Union of India and Another, (2005) 7 SCC 725 , and made a specific reference to the observations made in paragraphs 20, 21 and 22, which read as follows : "20. The competence of Parliament and the State Legislatures to repeal, amend h or supersede an exemption notification is unquestionable. The power to do so retrospectively cannot be and is also not doubted. The limitation on this power is that the legislation must not conflict with other provisions of the Constitution. As far as fiscal legislation is concerned, the limitation is implicit in article 265 of the Constitution which provides that no tax shall be levied or collected except by authority of law. As was held by this court in Chhotabhai Jethabhai Paid and. Co. v. Union of India: (SCR p. 30) "If by reason of article 265 every tax has to be imposed by 'law' it would appear to follow that it could only be imposed by a law which is valid by conformity to the criteria laid down in the relevant articles of the Constitution. Co. v. Union of India: (SCR p. 30) "If by reason of article 265 every tax has to be imposed by 'law' it would appear to follow that it could only be imposed by a law which is valid by conformity to the criteria laid down in the relevant articles of the Constitution. These are that the law should be (1) within the legislative competence of the Legislature being covered by the legislative entries in Schedule VII of the Constitution; (2) the law should not be prohibited by any particular provision of the Constitution such as, for example, articles 276(2), 286, etc., and (3) the law or the relevant portion thereof should not be invalid under article 13 for repugnancy to those freedoms which are guaranteed by Part III of the Constitution which are relevant to the subject-matter of the law." 21. A law cannot be held to be unreasonable merely because it operates retrospectively. Indeed even judicial decisions are in a sense retrospective. When a statute is interpreted by a court, the interpretation is, by fiction of law, deemed to be part of the statute from the date of its enactment. The unreasonability must lie in some other additional factors. The retrospective operation of a fiscal statute would have to be found to be unduly oppressive and confiscatory before it can be held to be so unreasonable as to violate constitutional norms: "Where for instance, it appears that the taxing statute is plainly discriminatory, or provides no procedural machinery for assessment and levy of the tax, or that it is confiscatory, courts would be justified in striking down the impugned statute as unconstitutional. In such cases, the character of the material provisions of the impugned statute is such that the court would feel justified in taking the view that, in substance, the taxing statute is a cloak adopted by the Legislature for achieving its confiscatory purposes." -- see Rai Ramkrishna v. State of Bihar, SCR p. 910. The question to be answered therefore is whether section 154, which is in terms retrospective, is ex facie discriminatory, or so unreasonable or confiscatory that it violates articles 14 and 19 of the Constitution. 22. The question to be answered therefore is whether section 154, which is in terms retrospective, is ex facie discriminatory, or so unreasonable or confiscatory that it violates articles 14 and 19 of the Constitution. 22. The factors which are generally considered relevant in answering this question are: (i) the context in which retrospectivity was contemplated, (ii) the period of such retrospectivity, and (iii) the degree of any unforeseen or unforeseeable financial burden imposed for the past period." 7. Sri Saikia, also relied upon the observations of the Supreme Court made in paragraph 32,33,35 and 43 of Shree Sidhbali Steels Ltd. and Others v. State of Uttar Pradesh and Others, (2011) 3 SCC 193 , which read as follows : "32. The doctrine of promissory estoppel is by now well recognised and well defined by a catena of decisions of this court. Where the Government makes a promise knowing or intending that it would be acted on by the promise and, in fact, the promisee, acting in reliance on it, alters his position, the Government would be held bound by the promise and the promise would be enforceable against the Government at the instance of the promisee notwithstanding that there is no consideration for the promise and the promise is not recorded in the form of a formal contract as required by article 229 of the Constitution. The rule of promissory estoppel being an equitable doctrine has to be moulded to suit the particular situation. It is not a hard-and-fast rule but an elastic one, the objective of which is to do justice between the parties and to extend an equitable treatment to them. This doctrine is a principle evolved by equity, to avoid injustice and though commonly named promissory estoppel, it is neither in the realm of contract nor in the realm of estoppel. For application of the doctrine of promissory estoppel the promisee must establish that he suffered in detriment or altered his position by reliance on the promise. 33. Normally, the doctrine of promissory estoppel is being applied against the Government and defence based on executive necessity would not be accepted by the court. For application of the doctrine of promissory estoppel the promisee must establish that he suffered in detriment or altered his position by reliance on the promise. 33. Normally, the doctrine of promissory estoppel is being applied against the Government and defence based on executive necessity would not be accepted by the court. However, if it can be shown by the Government that having regard to the facts as they have subsequently transpired, it would be inequitable to hold the Government to the promise made by it, the court would not raise an equity in favour of the promisee and enforce the promise against the Government. Where public interest warrants, the principles of promissory estoppel cannot be invoked. The Government can change the policy in public interest. However, it is well settled that taking cue from this doctrine, the authority cannot be compelled to do something which is not allowed by law or prohibited by law. There is no promissory estoppel against the settled proposition of law. Doctrine of promissory estoppel cannot be invoked for enforcement of a promise made contrary to law, because none can be compelled to act against the statute. Thus, the Government or public authority cannot be compelled to make a provision which is contrary to law. 35. A critical analysis of the abovequoted passage makes it evident that the two-Judge Bench in Sant Steels case was of the view that the notification issued under section 49 of the Act of 1948 can be revoked/modified only if express provision was made for the revocation/modification of the said notification under section 49 itself and the court found that as there was no such provision contained in section 49, it was not open to the Corporation to revoke the same. Further, though the court made reference to the General Clauses Act, it added that the provisions of the General Clauses Act would be applicable in case of delegated legislation if withdrawal/curtailment of benefit was in larger public interest or if the legislation was enacted by the Legislature authorising the Government to withdraw/curtail the benefit granted by a notification. Under the circumstances the two notifications curtailing the benefit to 17% were treated as contrary to section 49 of the Act of 1948. Under the circumstances the two notifications curtailing the benefit to 17% were treated as contrary to section 49 of the Act of 1948. On review of the law on the subject and the relevant statutory provisions, this court finds that, for the reasons mentioned hereinafter, the above statement of law is not an accurate proposition of law. 43. This court finds that the proposition of law laid down by the two-Judge Bench in the decision in Sant Steels case mentioned above is too wide and has tendency to make section 21 of the General Clauses Act, 1897, inoperative. The concept of the larger public interest introduced, before invocation of section 21 of the General Clauses Act, in fact, amounts to amendment of the said provision, as Notifications dated 18.6.1998 and 25.1.1999, issued under section 49 of the Act of 1948, as well as Notification dated 7.8.2000, issued under section 24 of the Uttar Pradesh Electricity Reforms Act, 1999, are in the nature of legislations and, therefore, the principle of promissory estoppel would not apply to them." 8. Sri Saikia, summarizing the ratio laid down in the said decisions, argued that the legislative power to amend the provisions of the Act retrospectively cannot be denied and if once any legislation is made with retrospective effect, it shall prevail over the executive notifications and the policy decisions of the executive. 9. In the instant case, the amendment is effected with retrospective effect. Therefore, the principle of promissory estoppel cannot be invoked against a statute and the law making power of the Parliament/State Legislature. Therefore, argued that the petitioners cannot contend that the provision of rule 57A is ultra vires and illegal. Upon thorough consideration of the facts and the submissions, we find that the rule 57A framed by way of delegated legislation is beyond the competence of the State. The definition of 'manufacture' in the Act clearly discloses that the process of manufacture would mean that the process of change in the product and bringing out a new product or combination of products in the process to bring out a new product would amount to manufacture. The process of making coal from coke will bring a new product from the coal; therefore, it amounts to manufacture within the definition of section 2(30) of the Act. The process of making coal from coke will bring a new product from the coal; therefore, it amounts to manufacture within the definition of section 2(30) of the Act. Under the guise of the rule making power, the State could not have amended the definition of 'manufacture' to omit or to alter the activities, which come within the definition of manufacture, that apart, the decision of the Supreme Court in Mahabir Vegetable Oils (P.) Ltd. case (supra) succinctly makes a distinction between the legislation and subordinate legislation and the limitation of subordinate legislation. Paragraphs 41 to 44 of Mahabir Vegetable Oils (P.) Ltd. case (supra) makes it clear that a delegated legislation cannot take away the right that is vested or accrued by way of retrospective amendment. Therefore, in view of the said reasons, we hold that the amended rule 57A(1) ultra vires the provisions of the definition of 'manufacture' under the Act and beyond the competence of rule making power to alter the definition of 'manufacture'. 10. There is serious dispute with regard to the date on which the industry was set up and it commenced the commercial production. The counsel for the State submits that the industry had established in 2005 and commenced production prior to the coming into effect the industrial policy of 2008; therefore, the units of the petitioners are not entitled to any concession under the policy. Per contra, the counsel for the petitioners submits that the units have been established and production commenced subsequent to the declaration of the industrial policy of 2008 and they are entitled to the benefit of the policy. These, disputes are basically questions of fact, which has to be resolved by the industries department where the application for grant of eligibility certificate is pending. Considering the facts and material and after giving fair opportunity to both the parties, this question of fact to be decided. Accordingly, the writ petitions are disposed of.