London

PricewaterhouseCoopers LLP was fined £5.1 million ($6.6 million) for misconduct over its audit of RSM Tenon Group Plc in the largest-ever sanction issued by the UK accounting regulator.

The Financial Reporting Council announced the fine Wednesday, along with penalties against Nicholas Boden, a senior PwC audit partner. The misconduct related to an audit of RSM’s accounts for the year ended June 2011. RSM is a professional services firm offering advice on taxes and risk. The record penalty comes only three months after PwC incurred another record fine for misconduct over its audit of Connaught Plc, a FTSE 250 company that went into administration in 2010. The FRC issued a 5 million-pound sanction against the auditor over the Connaught work in May, marking the then-largest-ever penalty from the regulator.