Note 9 – Significant Customers

Revenue for the three months ended March 31, 2019 and 2018 was $2.3 million and $3.4 million, respectively. Three third-party contract manufacturing customers accounted for 45.7%, 23.9% and 12.3%, respectively, of our revenue for the three months ended March 31, 2019. Two third-party contract manufacturing customers accounted for 48.2% and 33.2%, respectively, of our revenues for the three months ended March 31, 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 35% and 23% of our total trade receivable balances at March 31, 2019 and 82% of our total trade receivable balances at December 31, 2018, respectively.