Taxation

6 Months Ended

Jun. 30, 2015

Income Tax Disclosure [Abstract]

Income Tax Disclosure

21.       Taxation

The effective rate of tax for the three months to June 30, 2015 was -37% (2014: -51%) and for the six months to June 30, 2015 was 2% (2014: -19%).

The effective rate of tax is negative for the three months to June 30, 2015 and low for the six months to June 30, 2015 primarily due to the reduction in deferred tax liabilities in relation to the impairment of IPR&D intangible assets, the re-measurement of uncertain tax positions relating to ongoing tax audits and the release of certain valuation allowances all recognized during the second quarter.

The effective rate of tax in the three and six months to June 30, 2014 was negative primarily due to the recognition of a net tax credit in relation to the settlement of tax positions with the Canadian revenue authorities in the second quarter of 2014.