The petitioner is an industrial unit engaged in manufacturing and supply of Precured Tread Rubber (PCTR), Bonding Gum (BG) and Vulcanising Cement/Solution (BVC) etc. The petitioner is supplying the above products to different State Road Transport Organisations within the country. The 1st respondent Corporation, being an instrumentality of the State Government, is following the procedure prescribed in the 'Purchase Manual for procurement of materials' for all purchases made. Provisions contained in the Kerala Transparency in Public Purchase Act, 2002 is applicable to the 1st respondent. One of the methods contemplated under the said Act is to purchase materials directly from suppliers who are rate contractors approved by the 'Association of State Road Transport Undertakings (ASRTU)', New Delhi. The 1st respondent Corporation is a member of ASRTU. The Corporation took decision to purchase PCTR, DG and BVC only from holders of approved rate contract from ASRTU,