The Galactic Great Seal was the term given to the emblem of the Galactic Republic's Senate. In some cases, the Great Seal was surrounded by the individual seals of the Thousand Worlds. The most prominent Great Seal was found on the Chancellor's Podium in the Senate Rotunda.
The Republic Group stole the seal from the Podium while renovations were being completed, in a plot to eventually restore the Republic's honor. However, the seal they stole was in reality a fake as well; the real seal having been lost to time many years before.