Internal Revenue Service

The agency is challenging $21 billion in deductions over a three-year period (Getty)

IRS probes promoters of tax-deductible property easements

Agency challenging $21 billion in deductions over three-year period

Taxpayers in New York have four days to try beating cap on state, local deductions

Taxpayers in New York have four days to try beating cap on state, local deductions

IRS has moved to block charitable workarounds effective after August 27

IRS may be stepping up scrutiny of mortgage deductions

IRS may be stepping up scrutiny of mortgage deductions

The lack of crucial data points in the older 1098 form posed more challenges to the agency