Petronet MHB Limited (PMHBL) was incorporated on 31.07.1998 on common carrier principle to provide petroleum product transportation facility from Mangalore Refinery at Mangalore to the Oil Marketing Company Terminals at Hassan & Devangonthi (Bangalore). It was a Joint Venture promoted by M/s Petronet India Ltd., and M/s Hindustan Petroleum Corp. Ltd. with 26% equity by each company. After PMHBL underwent corporate debt restructuring in 2006, HPCL & ONGC are holding 29% equity each, consortium of nationalised banks is holding 34% equity and Petronet India Ltd. is holding 8% equity in the Company

PMHBL pipeline was envisaged to transport the petroleum products such as MS commonly known as petrol, HSD commonly known as diesel, SKO commonly known as Kerosene, Naphtha and aviation turbine fuel to meet the needs of various districts viz. Hassan, Mysore, Mandya, Tumkur, Chikmangalore, Chitradurga, Shimoga, Kolar, Bellary, Raichur, Ramanagara, Bangalore Rural & Bangalore Urban districts of Karnataka State. The total cost of the project was Rs. 640 crores. The main object was to transport petroleum product with high standard of quality measure and to render the best quality product to the customers through Oil Marketing Companies in order to reduce road / rail transportation and environmental pollution and also de-congestion of traffic in the highway.

PMHBL was incorporated to lay the pipeline as aforesaid which is first of its kind in transporting the petroleum product by underground pipeline in the state of Karnataka. The petroleum products are transported for a distance of 362.36 Km from Mangalore to Bangalore via Hassan.