Vanguard Group could be forced to raise its fees to cover new tax payments, University of Michigan law professor Reuven Avi-Yonah told Reuters. Avi-Yonah, hired as a tax expert for a plaintiff in a lawsuit against Vanguard, estimated tax authorities could claim the firm has an unmet liability of $35 billion from 2007 to 2014. Former Vanguard attorney David Danon has accused the firm of short-changing tax authorities by not charging funds the full price of its services. Read the original story from Reuters.