Accounts receivable and revenue concentrations

6 Months Ended

Jun. 30, 2012

Accounts Receivable and revenue concentrations [Abstract]

Accounts receivable and revenue concentrations

2. Accounts receivable and revenue concentrations

Two customers accounted for 24% and 57%, respectively, of gross accounts receivable as of June 30, 2012. Three customers accounted for 26%, 29% and 33%, respectively, of gross accounts receivable as of June 30, 2011.

Two customers accounted for 16% and 33% of total revenue for the three months ended June 30, 2012. Three customers accounted for 11%, 13%, and 23%, respectively, of total revenue for the three months ended June 30, 2011.

Two customers accounted for 7% and 15% of total revenue for the six months ended June 30, 2012. Four customers accounted for 10%, 11%, 12% and 12% of total revenue for the six months ended June 30, 2011.