Octan is the brand of fictional Legoland gas stations in the Town theme. It was first used in the 1990s, replacing the earlier Shell license (and even a brief Exxon license). The brand's color scheme is white with red and green stripes.
The fictional brand has been used to create themed sets like the World City Service Station (7993) in 2007. It has also been used as dressing in other themes and sets. For example barrels with the characteristic Octan colors appeared in the World City, Hovercraft Hideout (7045) and the Batcave (7783) from the Batman theme. The logo and name appeared as a "sponsors" sticker on such sets as the Speedboat (7244) and Scorpion Buggy (6602).
The LEGO Movie
In the The LEGO Movie Octan has become the largest mega-corporation in the LEGO Universe. The CEO, President Business, is the main villain of the movie.