The PCAOB says William Trainor improperly concluded he did not have to issue an adverse ICFR opinion for Forest Oil.
Requiring smaller companies to have their internal controls audited "may not be an efficient way of benefiting and protecting investors."
The companies allegedly failed to remedy material weaknesses in their internal controls over financial reporting for seven to 10 consecutive years.
Audit fees increased by a median of 3.2% in 2015, but the largest filers are keeping a lid on costs by improving internal controls.
A decline in accounting fraud has freed up time for SEC staff to prioritize internal controls over financial statements.
The oil company's former CFO failed to identify staffing problems in its accounting department as a material weakness, the SEC says.
