Big banks are trying to gain the upper hand in the race to electronify trading of collateralized loan obligations (CLOs), hoping to hold onto their role as key middlemen in a market that has more than doubled in size over the past decade.

Seven dealers have backed a new trading platform, called Octaura, that will combine Bank of America’s electronic trading system for loans with a CLO bidding protocol from Citi and data from Moody’s Analytics. The idea, the banks say, is to bring CLO trading