The British TV show Dragon's Den is based on the Japanese business reality programme Money Tigers.
Money Tigers, known in Japan as Manē no Tora, established the central format later used by Dragon's Den: entrepreneurs present business proposals to wealthy investors and seek funding in exchange for an ownership stake. The British adaptation retained the confrontational pitch-room structure while using its own panel, presenter and branding.
The format later spread internationally under different names. In the United States, the related version is Shark Tank, while many other countries use titles based on dragons or local investors. Dragon's Den is therefore not an entirely original British format, even though its BBC presentation and investor lineup made it especially recognisable in the UK.
A common mix-up is to identify Shark Tank as the source programme. Shark Tank is another adaptation of the same international format family, not the Japanese programme from which the British series directly derives.