NOTE 4. SIGNIFICANT CUSTOMERS AND CONCENTRATIONS OF CREDIT RISK

The Company’s ten largest customers by revenue accounted for approximately 49.7% and 52.1% of its net revenues in the three and six months ended June 30, 2018, respectively. The Company’s ten largest customers by revenue accounted for approximately 65.7% and 67.2% of its net revenues in the three and six months ended June 30, 2017, respectively.

The Company is potentially subject to concentrations of credit risk through its financial instruments, which consist primarily of cash and cash equivalents, marketable securities and accounts receivable. The Company limits its exposure to credit loss by placing its cash with high credit quality financial institutions. At times, such deposits may be in excess of insured limits. The Company has not experienced any losses on its deposits of cash and cash equivalents. The Company typically invests in highly-rated securities, and its investment policy generally limits the amounts that may be invested with any one issuer. The policy generally requires investments to be investment grade, with the primary objective of minimizing the potential risk of principal loss.