We have not provided for U.S. federal or foreign income taxes, including withholding taxes on $14.0 billion of our non-U.S. subsidiaries' undistributed earnings as of December 31, 2013. We intend to indefinitely reinvest the $14.0 billion of our non-U.S. subsidiaries' undistributed earnings in our international operations. Accordingly, we currently have no plans to repatriate those funds. As such, we do not know the time or manner in which we would repatriate those funds. Because the time or manner of repatriation is uncertain, we cannot determine the impact of local taxes, withholding taxes and foreign tax credits associated with the future repatriation of such earnings and therefore cannot quantify the tax liability. In cases where we intend to repatriate a portion of our foreign subsidiaries' undistributed earnings, we provide U.S. and applicable foreign taxes on such earnings and such taxes are included in our deferred taxes or tax payable liabilities depending upon the planned timing and manner of such repatriation. During 2013, we provided U.S. tax on approximately $450 million of our non-U.S. earnings which we expect to repatriate in the future.

On a regular basis, we develop cash forecasts to estimate our cash needs internationally and domestically. We consider projected cash needs for, among other things, investments in our existing businesses, potential acquisitions and capital transactions, including repurchases of our common stock and debt repayments. We estimate the amount of cash available or needed in the jurisdictions where these investments are expected, as well as our ability to generate cash in those jurisdictions and our access to capital markets.

This analysis enables us to conclude whether or not we will indefinitely reinvest the current period's foreign earnings. We benefit from tax rulings concluded in several different jurisdictions, most significantly Switzerland, Singapore and Luxembourg. These rulings provide for significantly lower rates of taxation on certain classes of income and require various thresholds of investment and employment in those jurisdictions. These rulings resulted in a tax savings of $540 million and $439 million in 2013 and 2012, respectively, which increased earnings per share (diluted) by approximately $0.41 and $0.33 in 2013 and 2012, respectively. These tax rulings are currently in effect and expire over periods ranging from 2020 to the duration of business operations in the respective jurisdictions. We evaluate compliance with our tax ruling agreements annually.

The determination of our worldwide provision for income taxes and other tax liabilities requires estimation and significant judgment, and there are many transactions and calculations where the ultimate tax determination is uncertain. Like many other multinational corporations, we are subject to tax in multiple U.S. and foreign tax jurisdictions and have structured our operations to reduce our effective tax rate. Our determination of our tax liability is always subject to audit and review by applicable domestic and foreign tax authorities, and we are currently undergoing a number of investigations, audits and reviews by taxing authorities throughout the world, including with respect to our tax structure. Governments are increasingly focused on ways to increase revenues, which has contributed to an increase in audit activity and harsher stances taken by tax authorities. Any adverse outcome of any such audit or review could have a negative effect on our business, operating results and financial condition, and the ultimate tax outcome may differ from the amounts recorded in our financial statements and may materially affect our financial results in the period or periods for which such determination is made. While we have established reserves based on assumptions and estimates that we believe are reasonable to cover such eventualities, these reserves may prove to be insufficient in the event that any taxing authority is successful in asserting tax positions that are contrary to our positions.

In light of serious ongoing fiscal challenges in the U.S. and many countries in Europe, various levels of government are also increasingly focused on tax reform and other legislative action to increase tax revenue, including corporate income taxes. For example, the economic downturn reduced tax revenues for U.S. federal and state governments, and a number of proposals to increase taxes from corporate entities have been implemented or are being considered at various levels of government. Among the options have been a range of proposals included in the tax and budget policies recommended to the U.S. Congress by the U.S. Department of the Treasury to modify the federal tax rules related to the imposition of U.S. federal corporate income taxes for companies operating in multiple U.S. and foreign tax jurisdictions.

If such proposals are enacted into law, this could increase our effective tax rate. A number of U.S. states have likewise attempted to increase corporate tax revenues by taking an expansive view of corporate presence to attempt to impose corporate income taxes and other direct business taxes on companies that have no physical presence in their state, and taxing authorities in foreign jurisdictions may take similar actions. Many U.S. states are also altering their apportionment formulas to increase the amount of taxable income/loss attributable to their state from certain out-of-state businesses. Companies that operate over the Internet, such as eBay, are a target of some of these efforts. If more taxing authorities are successful in applying direct taxes to Internet companies that do not have a physical presence in the jurisdiction, this could increase our effective tax rate.

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