Note 9 – Significant Customers

Revenue for the three months ended June 30, 2019 and 2018 was $1.7 million and $3.2 million, respectively. Two third-party contract manufacturing customers accounted for 67.2% and 21.2%, respectively, of our revenue for the three months ended June 30, 2019. Two third-party contract manufacturing customers accounted for 57.2% and 29.4%, respectively, of our revenue for the three months ended June 30, 2018. The loss of sales to either of these large third-party contract manufacturing customers could have a material adverse effect on our business operations and financial condition.

Revenue for the six months ended June 30, 2019 and 2018 was $4.0 million and $6.6 million, respectively. Two third-party contract manufacturing customers accounted for 54.8% and 22.8%, respectively, of our revenue for the six months ended June 30, 2019. Two third-party contract manufacturing customers accounted for 43.1% and 39.0%, respectively, of our revenue for the six months ended June 30, 2018. The loss of sales to either of these large third-party contract manufacturing customers could have a material adverse effect on our business operations and financial condition.

We are subject to account receivable credit concentrations from time-to-time as a consequence of the timing, payment pattern and ultimate purchase volumes or shipping schedules with our customers. These concentrations may impact our overall exposure to credit risk, either positively or negatively, in that our customers may be similarly affected by changes in economic, regulatory or other conditions that may impact the timing and collectability of amounts due to us. Two customers represented 45% and 39% of our total trade receivable balances at June 30, 2019 and 82% of our total trade receivable balances at December 31, 2018, respectively.