At least five investment banks are vying to win a mandate from Banca Popolare di Milano (BPM) (PMII.MI) and find it a partner as Italian cooperative lenders gear up for a wave of mergers following a landmark reform of the sector. The Milanese bank, Italy’s seventh-largest by branches, has been dubbed by industry watchers the “belle of the ball” among large cooperative lenders that are looking at tie-up options as they are being forced to drop their cooperative status.