That form instructs you to enter IRC Section 179 deductions and special allowances. Section 179 allows eligible businesses to deduct the full purchase price of qualifying equipment in the year it was put into service.Generally, the basis will be the purchase price of the property, plus any capital expenditures, minus any rebates and IRC Section 179 expense. Use Form 4797 to report: The sale or exchange of property. The involuntary conversion of property and capital assets. Section 179 potentially allows significant first-year depreciation deductions when your business places qualifying assets into service. This item addresses how S corporations and partnerships that have a Sec. 179 recapture event should report the event to their owners.