‘Green addresses’ were proposed as a way to bypass long confirmation times by relying on a reputable entity’s guarantee. If you receive funds from a ‘green address,’ it might imply a bank-like institution has verified and will vouch for the transaction, reducing the risk of double spend.

Critics argue it centralizes trust: you’re effectively relying on a single service to promise they won’t reverse the transaction. It undermines Bitcoin’s decentralized ethos by introducing a gatekeeper. While not widely adopted, the idea persists in various forms of ‘fast confirmations’ provided by certain wallets or payment processors that trust user deposits.