The Post merger trading symbol is SIRI
http://finance.yahoo.com/q?s=siri
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"SIRIUS and XM Complete Merger"
http://investor.sirius.com/releasedetail.cfm?ReleaseID=324858
NEW YORK, July 29, 2008 /PRNewswire-FirstCall via COMTEX News Network/ -- SIRIUS Satellite Radio (Nasdaq: SIRI) and XM Satellite Radio today announced that they have completed their merger, resulting in the nation's premier radio company. The new company plans to change its corporate name to SIRIUS XM Radio Inc. The combined company's stock will continue to be traded on the Nasdaq Global Select Market under the symbol "SIRI."
XM shareholders will receive 4.6 shares of SIRIUS common stock for each share of XM.
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Contact your Broker,,,but your account should show an open position in SIRI