The $4.5B sale of Nortel's patents to six tech companies (AAPL, MSFT, RIMM, EMC, ERIC, and SNE) is still being reviewed by the DOJ, according to Microsoft's IP chief. Regulatory challenges to the deal could potentially have an impact on the bidding for InterDigital (NASDAQ:IDCC) and/or Eastman Kodak's (EK) patents.