What was the Japanese television format adapted into the UK series Dragon's Den?

The Japanese television format adapted into the UK series Dragon's Den was Money Tigers.

Money Tigers was a Japanese business reality programme in which entrepreneurs presented proposals to potential investors. The British version retained the central idea: founders make a direct pitch, answer questions and negotiate for investment or leave without a deal.

The format was created in Japan before being adapted for several countries. In the United Kingdom, the name Dragon's Den reflected the intimidating image of the investors, who are commonly called Dragons rather than sharks or tigers.

A common mix-up is to identify Shark Tank as the original source. Shark Tank is the later American adaptation of the same broad international format, while Money Tigers is the Japanese programme credited as the original source for Dragon's Den.