From The Tax Adviser: Section 179 Revisited.

The article focuses on section 179 of the U.S. Internal Revenue Code. Under section 179, taxpayers can elect to treat some or all of the cost of qualifying assets, up to $17,500, as a current expense rather than as property eligible for depreciation. The amount of this deduction is reduced, dollar for dollar, by the total cost of property placed in service that exceeds $200,000. This election is made on Form 4562, Depreciation and Amortization; employees can use Form 2106, Employee Business Expenses. It must be made on the first return for the tax year to which the election applies, that is, the tax year the property was placed in service. This provision has an annual expense limit of $17,500. For pass-through entities, this dollar limitation applies at both the entity and partner level. However, in applying the $200,000 total property limit, eligible property placed in service by the entity is not attributable to the partner or shareholder. If the business use of qualifying property falls below 50% before the end of the property's recovery period, any benefit derived from a section 179 election must be recaptured as ordinary income in the year the property no longer qualifies.