The W221 S-Class' exterior styling is distinctly different from the W220. The W220 somewhat broke with tradition in being smaller than its W140 predecessor, whereas the W221 is once more larger in all dimensions than its predecessor, offers more interior space and has improved performance. The W221 looks are often said to be more imposing than those of the W220. The rear styling is similar to the Mercedes-Benz Maybach – the larger saloon from Daimler AG's other flagship brand, which was presented to the public in 1997. Development began in 1999, with the design work beginning in 2000 at the Advanced Design Center in Tokyo, and the final design by Gorden Wagener at the Sindelfingen Advanced Design Center being approved in 2001, frozen for production in early 2002 and patented in Japan on May 21, 2003, under 1208488 and in Germany on December 4, 2003. A final design prototype W221 was presented in December 2002 to Autospies journalists at a consumer design clinic, 2.5 years prior to the official production model unveiling in June 2005.