JUDGMENT

Sethi, J.-Leave granted in SLP (C) No. 3297 of 1998.

2. As the point of law involved in both the cases are identical, they are being disposed of by this common judgment.

3. The appellants who had set up their own generating units for the supply of electrical energy in the State of Madhya Pradesh have claimed the benefit of Notification No. F.10-7-XIII-81 dated 13th March, 1981 issued under Section 3B of the Madhya Pradesh Electricity Duty Act, 1949 (hereinafter referred to as "the Act") exempting with effect from 10th December, 1980 all producers who run industries from payment of duty during the period as specified in the Scheduled attached therewith. The writ petitions filed by the appellants were dismissed by the High Court vide the impugned order holding that only such producers who had set up the generating units after 10.12.1980 were entitled to the exemption granted vide aforesaid notification.

4. It is contended on behalf of the appellants that the notification was applicable to all producers who run industries by establishing their own generating stations for the purposes of consumption of electrical energy notwithstanding as to whether they had started generating the electricity after or prior to 10.12.1980. In order to appreciate the contentions raised on behalf of the appellants, it is necessary to have a look at the notification, the benefit of which is claimed by the appellants. The Notification provides:

"Whereas the State Government is of opinion that having regard to the particular circumstances of the industries establishing their own generating station for purposes of consumption of electrical energy by such industries, it is necessary and expedient so to do in the public interest;

Now, therefore, in exercise of the powers conferred by Section 3-B of the Madhya Pradesh Electricity Duty Act, 1949 (No. X of 1949), the State Government hereby exempts with effect from the 10th December, 1980 all producers who run industries (from payment of duty, during the period as specified in column (1) of the Schedule below and to the extent as specified in the corresponding entries in column (2) thereof, in respect of the electrical energy consumed by such producers for the purposes of the industries run by them."

Such a notification has been issued under Section 3B of the Act which provides as:

"3B. Power to exempt.-Where the State Government is of opinion that-

(i) in order to encourage the establishment of any particular industry or class of industries in the State; or

(ii) having regard to the particular circumstances of any industry or class of industries; or

(iii) in order to extend facilities to such persons or class of persons and for such purposes as the State Government may, by notification, specify;

it is necessary or expedient so to do in public interest, it may, by notification and subject to such conditions, if any, as it may specify in the notification.-

(a) exempt from payment of duty in whole or in part-

(i) any distributor of electrical energy or producer in respect of the electrical energy sold or supplied to such industry for the purposes thereof;

(ii) Where any producer or class of producers runs the industry, in respect of the electrical energy consumed by such producer or class of producers for the purpose of such industry;

(iii) any distributor of electrical energy or producer in respect of the electrical energy sold to or used for consumption by person or class of persons and for purposes of specified in the notification;

(b) cancel any such notification and again subject, by a like notification, the distributor of electrical energy or producer or class of such producers to the payment of such duty in respect of such sale, supply or consumption of electrical energy."

It is settled position of law that exemption notification particularly in a fiscal matters h