The Lego System logo from 1992 onwards.
LEGO System is the brand under which most standard minifigure-compatible sets are marketed since 1978. It is the LEGO Company's main line of building elements, minifigures and sets. The pieces in this line are smaller than Duplo blocks. The iconic logo of LEGO System wasn't featured on boxes and catalogues until 1992. Most newer minifigure-compatible sets don't feature this logo anymore although they are still considered a part of System, including Atlantis.
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