theodp writes: The Financial Times reports that Microsoft's foreign tax planning has come under the scrutiny of US securities regulators, who have prodded the software giant into disclosing details of how it uses foreign tax planning to reduce its US taxes. FT reports that the SEC also forced the company to reveal that the bulk of its $50.2 billion cash mountain — $42 billion — is held outside the US. Microsoft and a growing number to companies — including Google, Cisco, IBM, and Dell — are taking advantage of a bond sellers' market and opting to leave cash overseas and borrow to meet domestic needs. Don't cast stones, Apple fans — folks are also iRate about Apple, which has joined forces with Microsoft and a who's who of high tech to support the Win America campaign, which calls for 'an immediate reduction of taxation' to allow Corporate America to bring back $1 trillion 'trapped overseas' to be 'brought home and invested in the United States.' So what to do in the meantime with all that offshore loot which, as Microsoft put it, is 'subject to material repatriation tax effects'? Invest in the United States, apparently. According to Microsoft's recent correspondence with the SEC: 'Approximately 63% of foreign subsidiary short-term investments were invested in U.S. Government and Agency securities, approximately 14% were invested in corporate notes and bonds of U.S. companies, and 10% were invested in U.S. mortgage backed securities.'