> For the complete documentation index, see [llms.txt](https://hub.bsvblockchain.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hub.bsvblockchain.org/wiki/transactions-and-utxos/bitcoin-transactions/double-spending.md). # Double-spending 1. Definition Double-spending is the act of sending a transaction containing inputs that have already been spent, in an attempt to commit fraud on the network. 2. Consequences Double spends are one of the most commonly discussed attacks on Bitcoin, however there has yet to be a documented case of someone executing a successful double-spend using Bitcoin in commerce. The reason for this is that double-spending is a crime and analogous to intentionally bouncing a check - the difference is that the merchant would have cryptographic proof that the customer attempted such an act. 3. Economic incentives Bitcoin solves the double-spending problem via its economic incentives. Miners have a strong incentive not to include these transactions in a block because they are at risk of having their block rejected by other Miners, and in addition, would be complicit in carrying out a crime. These factors highlight why the solution to double-spending is an economic solution, not a technical one. Many arguments have been made by developers in the past that changes are necessary to the protocol to fix this issue, but they have been deemed unnecessary. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://hub.bsvblockchain.org/wiki/transactions-and-utxos/bitcoin-transactions/double-spending.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.