What is the official punctuation in the title of the UK television programme, Dragons' Den?

The official title uses a plural possessive apostrophe: Dragons' Den.

“Dragons” is plural because the programme features several investors, and the apostrophe comes after the s to show possession. The title therefore describes the den belonging to multiple Dragons. The BBC's English-language title is styled as Dragons' Den, although people often write or say “Dragon's Den” informally.

This is a grammar and branding distinction rather than a difference in the programme's format. The series still concerns entrepreneurs pitching to a panel of investors, and the title is shared in related forms by adaptations in other countries.

The common error is placing the apostrophe before the s, which would make “Dragon's” singular possessive and imply one Dragon. Omitting the apostrophe altogether is also not the standard title styling. The plural possessive form is the canonical British programme name.