The following table provides a reconciliation of Non-GAAP net income and Non-GAAP diluted income per share to net income and income per share - diluted, the most comparable GAAP financial measures (in thousands, except per share amounts): | ||||||||||||
(Unaudited) | ||||||||||||
Three Months Ended
March 31, | ||||||||||||
2019 | 2018 | |||||||||||
Net income | $ | 13,019 | $ | 24,684 | ||||||||
Stock-based compensation expense | 1,212 | 216 | ||||||||||
Amortization of intangible assets | 3,528 | 1,940 | ||||||||||
Acquisition related deferred revenue (1) | 2,250 | - | ||||||||||
Special adjustments (2) | 228 | (1,152 | ) | |||||||||
Income tax effect of non-GAAP adjustments (3) | (54 | ) | - | |||||||||
Non-GAAP net income | $ | 20,183 | $ | 25,688 | ||||||||
Income per share - diluted | $ | 0.17 | $ | 0.34 | ||||||||
Non-GAAP income per share - diluted | $ | 0.26 | $ | 0.35 | ||||||||
GAAP diluted shares outstanding: | 76,720 | 72,390 | ||||||||||
Non-GAAP diluted shares outstanding: | 77,700 | 72,800 | ||||||||||
(1 | ) | Represents revenue not recognized under GAAP due to acquisition accounting adjustment associated with the accounting for deferred revenue in significant business combinations.
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(2 | ) | Includes an impairment charge for royalty contracts resulting in $0.2 million and $0.9 million of expense for the three months ended March 31, 2019 and 2018, respectively. Includes a non-recurring adjustment for a change in estimated legal expenses resulting in $2.0 million of income for the three months ended March 31, 2018.
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(3 | ) | The income tax effect of non-GAAP adjustments for 2018 is affected by the U.S. valuation allowance. |