ITC today reported a 15% increase in net profit at Rs 536.83 crore for the third quarter ended December 31, 2005 when compared with Rs 466.70 crore in Q3FY05.According to a release issued by the company to the BSE today, total income increased to Rs 2,604.92 crore in Q3FY06 from Rs 1.911.12 crore in Q3FY05.