Law firm Maurice Blackburn says it will investigate the adequacy of compensation offered by National Australia Bank to its financial advice customers amid ongoing concerns that Macquarie Group is denying clients compensation by defining advice too narrowly. John Berrill, a principal at Maurice Blackburn, which is representing victims of advice scandals at Commonwealth Bank of Australia and Macquarie Private Wealth, said the firm had received calls on Monday from customers of NAB Wealth after Fairfax Media revealed at the weekend that NAB had paid $10 million to $15 million in compensation over five years to 750 customers who received inappropriate advice.