Do you buy or lease computer software to use in your business? Do you develop computer software for use in your business, or for sale or lease to others? Then you should be aware of the complex rules that apply to determine the tax rules for deducting software, whether you're buying, leasing or developing. Purchased software Some software costs are deemed to be costs of “purchased” software, meaning software that’s either: Non-customized software available to the general public under a non-exclusive license or Acquired from a contractor who is at economic risk should the software not perform.  The entire cost of purchased software can be deducted in the year that it’s placed into service. The cases in which the costs are ineligible for this immediate write-off are the...