NOTE 3—PATENTS AND DOMAIN NAME

We acquired patents from STI as a result of an asset contribution, and recorded them at their carryover basis. In June 2013, when STI exchanged its membership interest in Resonant LLC for a subordinated convertible note, the only assets of Resonant LLC other than cash were patents. The fair value of the patents remained substantially the same as their carrying value at the exchange date. In addition, we acquired other patents and the domain name www.resonant.com through the normal course of business. Issued patents are amortized over their approximate useful life of 17 years, or 20 years in the case of new patents, once they are approved by their respective regulatory agency. For the patents acquired from STI, we are amortizing them over the remaining useful life of 2 to 14 years as of December 31, 2104. The domain name is amortized over the approximate useful life of 10 years. See the table below for a summary of patents (issued and pending) and domain name costs capitalized and amortized at December 31, 2013 and December 31, 2014:

Amortization expense for the patents issued and the domain name for each of the five fiscal years through December 31, 2019 and thereafter is estimated as follows: