The Public Company Accounting Oversight Board (PCAOB) fined a Colorado-based audit firm and its founding partner a total of $150,000 for alleged professional skepticism failures and improperly altering audit documentation.

The regulator also revoked the registration of the firm, AJ Robbins CPA, and permanently barred its managing partner and owner, Allan Jeffrie Robbins, from association with any registered public accounting firm, the PCAOB announced Thursday.