ectrum that they do not use or that is vastly underused. Mobile and Wi-Fi Networks Regulating the Amount of Spectrum per Carrier by Using Spectrum Screens Governments often establish policies limiting the amount of spectrum that any one carrier can have rights to in any single area. These limits, referred to as spectrum caps, are created to promote competition by splitting up air rights among carriers. At one time, the FCC had a spectrum cap of 55MHz per metropolitan area for mobile carriers. The federal government, under the Clinton administration, eliminated the cap in 2003. In place of the 55MHz spectrum caps, the FCC instituted spectrum screens of 95MHz. The new rule applies only to spectrum acquired through proposed mergers between carriers. In cases where the proposed merger results in a merged carrier with more than 95MHz of spectrum in a single region, the FCC can determine if this creates an anti-competitive situation. If it does determine that the merger is anti-competitive, it can order that the dominant carrier divest itself of spectrum in areas where it exceeds the 95-MHz screen. Eliminating the cap removed a stumbling block that would have prevented the merger of AT&T Wireless and Cingular (into AT&T Mobility) and the merger of Veri- zon Wireless with Alltel in the United States. It also eliminated rules which would have prohibited both Verizon and AT&T from leasing additional spectrum for certain regions at future auctions. Both Verizon and AT&T Mobility exceeded the 95MHz screen when they acquired 700MHz spectrum in 2008. This was approved because screen caps do not apply when spectrum is gained at auctions. Synchronizing Spectrum Internationally Spectrum allocation is administered on both an international and a national level. The International Telecommunications Union (ITU) manages the allocation of spectrum for services such as satellite and television that cross national borders. It also acts as the umbrella for other services such as determining spectrum bands for third- fourth-generation ser