State-owned gas utility GAIL (India) Ltd on Tuesday reported a 56 per cent jump in its September quarter net profit as bumper earnings from gas transmission and marketing business offset petrochem losses. Standalone net profit of Rs 2,404.89 crore in July-September, or Rs 3.66 per share, was 54.4 per cent higher than Rs 1,537.07 crore, or Rs 2.34 a share, profit in the same period last year, according to the company’s stock exchange filing.