Dragon's Den is based on the Japanese business programme Money Tigers.
Money Tigers supplied the core format: entrepreneurs present business ideas to a panel of wealthy investors and negotiate for finance. The Japanese concept was adapted for several territories, with local names, investors and production styles.
The British version began in 2005 and calls its investors dragons rather than tigers. That terminology reflects the programme’s title and its theatrical image of formidable businesspeople deciding whether a pitch deserves investment.
Viewers sometimes identify Shark Tank as the source because it has a very similar pitch-and-equity structure. Shark Tank is an American adaptation of the same broader format, not the direct Japanese programme named as Dragon's Den’s origin.