Regulators are studying whether asset managers are systemically important, without yet defining how to identify an institution within the sector that fits the bill. Asset managers, meanwhile, insist they are not systemically important, regardless of how that term is defined.

The result is two constituencies trading blows in the dark, with regulators fearful that the industry might pose a systemic risk in the future even if it has not done so in the past and asset managers resisting regulations that have not yet taken shape.