** Shares of Aussie Broadband ABB.AX rise as much as 19.9% to A$5.43 in early trade, their largest intraday pct gain since late August 2025
** Stock hits highest level since November 18, among top gainers on broader benchmark .AXJO
** Telecom firm signs agreement to buy the telecommunications business of power producer AGL Energy AGL.AX
** Says consideration includes upfront payment of A$115 million ($81.31 million) in ABB shares
** Adds co signs agreement with AGL for long-term exclusive partnership
** More than 1.2 million shares change hands, 1.2 times the 30-day average
** Stock up 3.2% YTD, including the day's moves
($1 = 1.4144 Australian dollars)
(Reporting by Nikita Maria Jino in Bengaluru)
((Nikita.Jino@thomsonreuters.com;))