Filtron Engineers surged 10% to hit upper circuit at ₹14.06 after acquiring 100% of Gabrielle Infra, a construction firm with FY25 turnover of ₹72.24 crore. The company also approved equity and preference share issues to raise ₹15.9 crore and plans to hike authorised share capital from ₹3.5 crore to ₹85 crore, marking its construction sector entry.