Anthem Biosciences will debut on stock exchanges on Monday, July 21, with grey market signals suggesting a potential 29% listing gain over its Rs 570 IPO price. The Rs 3,395 crore OFS-only issue closed on July 16 with strong demand, garnering 67.42 times overall subscription, led by QIBs (192.80x), NIIs (44.70x), and retail (5.98x).