The British Dragons' Den is based on the original Japanese business show format Money Tigers.
Money Tigers was the Japanese programme that established the format later adapted for television audiences around the world. Entrepreneurs presented business proposals to a panel of potential investors, who assessed the idea, questioned the presenter and decided whether to offer money for a stake in the company.
The British adaptation retained the basic dramatic structure while giving it a specifically British identity. Its investors are called dragons, and contestants usually frame their requests around a precise cash sum and percentage of equity. That combination makes valuation and negotiation as important as the product itself.
Money Tigers is often confused with Shark Tank because both shows belong to the same international family of formats. The British title, however, is Dragons' Den, and its format lineage is traced to Japan rather than to an independently created British reality show.