Intangible assets at September 30, 2017 and December 31, 2016 consist of the following:

Under the previous contract manufacturing agreement between ADMA and BPC, intermediate by-products derived from the manufacture of RI-002 were property of Biotest. As a result of the transaction, ADMA now has the right to these intermediate products. The customer contract pertains to a contract manufacturing agreement with a third party that the Company assumed upon the completion of the acquisition of the Biotest Assets. Amortization expense related to these acquisition-related intangible assets for the three and nine months ended September 30, 2017 was $0.3 million. Estimated aggregate future aggregate amortization expense for the next five years is expected to be as follows: