The Company’s intangible assets consist of customer relationship intangibles, trade names, licenses for the use of internet domain names, URL’s, software, and marketing and technology related intangibles. All such assets are capitalized at their original cost and amortized over their estimated useful lives as follows: domain name and marketing – 3 to 20 years; software – 3 to 5 years, customer relationships – 7 to 15 years. When certain events or changes in operating conditions occur, an impairment assessment is performed and lives of intangible assets with determined lives may be adjusted. Intangible amortization expense is $236,318 and $98,084 for the three months ended March 31, 2018 and 2017, respectively. Intangible amortization expense is $475,970 and $159,581 for the six months ended March 31, 2018 and 2017, respectively.

The following table summarizes estimated future amortization expense related to intangible assets that have net balances as of March 31, 2018: