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| Share-based compensation | 
 Note 10 — Share-based compensation 
 The following table shows the total share-based compensation expense included in the unaudited consolidated statements of operations (thousands): 
 
 
 There were 8,756,211 and 2,414,576 options over ordinary shares granted in the three months ended September 30, 2017 and 2016, respectively, with a weighted average fair value of $0.34 and $0.74, respectively. There were 28,959,363 and 17,758,373 options over ordinary shares granted in the nine months ended September 30, 2017 and 2016, respectively, with a weighted average fair value of $0.34 and $0.74, respectively. There were 74,145,505 and 49,237,290 share options outstanding at September 30, 2017 and December 31, 2016. 
 At September 30, 2017, there were 3,224,600 share options granted to nonemployees outstanding. Share-based compensation expense relating to non-employee options was an expense of $297,000 and a benefit of $24,000 in the three months ended September 30, 2017 and 2016, respectively, and an expense of $401,000 and a benefit of $139,000 in the nine months ended September 30, 2017 and 2016, respectively. 
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