18. Revenues from Contracts and Significant Customers

Disaggregation of Total Revenue

Product revenue is comprised of Journey’s five marketed products: Targadox®, Luxamend®, Ceracade®, Exelderm® and Ximino®. Substantially all of the product revenue is recorded in the U.S. The Company’s related party revenue is from Checkpoint’s collaboration with TGTX. The table below summarizes the Company’s revenue for the three months ending March 31, 2020 and 2019:

Significant Customers

For the three months ended March 31, 2020, two of the Company's Dermatology Products customers accounted for more than 10.0% of its total gross product revenue in the amount of $7.7 million and $5.1 million.

For the three months ended March 31, 2019, one of the Company’s Dermatology Products customers accounted for more than 10.0% of its total gross product revenue in the amount of $19.9 million.

At March 31, 2020, two of the Company’s Dermatology Products customers accounted for more than 10.0% of its total accounts receivable balance in the amount of $5.4 million and $2.5 million.

At March 31, 2019, one of the Company’s Dermatology Products customers accounted for more than 10.0% of its total accounts receivable balance in the amount of $7.7 million.