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26 U.S. Code § 212 - Expenses for production of income

In the case of an individual, there shall be allowed as a deduction all the ordinary and necessary expenses paid or incurred during the taxable year—
for the production or collection of income;
for the management, conservation, or maintenance of property held for the production of income; or
in connection with the determination, collection, or refund of any tax.
(Aug. 16, 1954, ch. 736, 68A Stat. 69.)
Statutory Notes and Related Subsidiaries
Denial of Deduction for Amounts Paid or Incurred on Judgments in Suits Brought To Recover Price Increases in Purchase of New Principal Residence

No deductions to be allowed in computing taxable income for two-thirds of any amount paid or incurred on a judgment entered against any person in a suit brought under section 208(b) of Pub. L. 94–12, see section 208(c) of Pub. L. 94–12, set out as a note under section 44 of this title.