Identity thieves continue to become increasingly sophisticated. The IRS noted an increase in fake filings for C corporations, S corporations, partnerships, and returns from trusts and estates. Forms 1120, 1120S, 1041, and Schedule K-1 are all affected by the rise in fraud.

Cybercriminals are using stolen Employer Identification Numbers (EINs) to file fake returns. The IRS has asked businesses to contact the IRS if extension requests were denied because of duplicate EIN numbers or if they receive tax transcripts or other notices from the IRS that they did not request.