Ruby Design Bureau (full name: Ruby Central Design Bureau for Marine Machinery, конструкторское бюро "Рубин") is one of the three largest submarine design bureaus in Russia, headquartered in St. Petersburg, and is the design bureau with the largest number of submarine classes and construction. It is one of the three largest submarine design bureaus in Russia. In addition to designing and building submarines, Ruby Design Bureau also designs and builds offshore oil and gas drilling platforms and other civilian projects.