XOMA Corporation Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Income Taxes

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2013
Income Taxes [Abstract]
Income Taxes	7. Income Taxes The Company did not recognize any income tax expense for the three months ended March 31, 2013 and 2012. The Company's effective tax rate will fluctuate from period to period due to several factors inherent in the nature of the Company's operations and business transactions. The factors that most significantly impact this rate include the variability of licensing transactions in foreign jurisdictions.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

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+ Details