In Dragons' Den, what is the name of the agreement that gives an investor the right to match a future offer?

In Dragons' Den, an agreement giving an investor the right to match a future offer is called a right of first refusal.

A right of first refusal allows its holder to respond before an owner sells an asset or stake to someone else. In a business deal, the clause can give an investor an opportunity to match an outside offer for shares or other interests before the seller accepts that offer.

This is different from a non-disclosure agreement, which controls confidential information, and from a trade licence, which permits a regulated activity. A right of first refusal also differs from a right of first offer: the latter usually requires an owner to approach the holder first, before seeking outside bids, rather than giving a matching right to an already-made offer.

Television deals may include such rights as part of negotiation, but the exact effect depends on the final written contract. A handshake in the den is not a substitute for signed legal documents.