"Back-end awards or bonus arrangements generally provide for contingent compensation based on preset asset or revenue targets extending over multiyear periods. The DOL is concerned that these types of awards 'significantly increase conflicts of interest for the advisers [dealing with retirement investors] . . . particularly as the adviser approaches the target' because the awards 'commonly result in large amounts of income to the adviser . . . on an 'all or nothing' basis.' Based on the concern above, the DOL concludes that 'financial institutions generally may not enter into such arrangements' when relying on the full BIC Exemption."