The maximum number of Dragons who can make a joint investment in one Dragons' Den pitch is five.
The British programme normally presents five investors on the panel in a pitch room. If all five agree that a proposal is attractive and the entrepreneur accepts the terms, they can participate together in a joint offer. In practice, many pitches produce no offer, a single-investor deal or a smaller group negotiation.
This number refers to the standard panel capacity, not to the number of investors who have appeared across the programme’s entire history. Guest Dragons and replacements have expanded the roster of people associated with the series, but only the investors present in a particular episode can make that episode’s offer.
Deals shown on television are also subject to due diligence and may later change or fail to complete. That production caveat does not alter the panel’s maximum of five possible participating Dragons.