> For the complete documentation index, see [llms.txt](https://docs.allforone.app/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.allforone.app/glossary/definitions/self-custody-wallets/shamirs-secret-sharing.md). # Shamir's Secret Sharing **Shamir's Secret Sharing** (SSS) is a method for dividing a secret into multiple pieces, called shares, such that a specified minimum number of shares (called the threshold) are required to reconstruct the original secret. This can be useful in the context of [seed phrases](/glossary/definitions/self-custody-wallets/seed-phrases.md) for secure backup and recovery of [self-custody wallets](/glossary/definitions/self-custody-wallets.md). For example, let's say you have a secret 12-word seed phrase for your bitcoin wallet, and you want to use Shamir's secret sharing to divide it into five shares. You could divide the seed phrase into five shares such that any three of the shares are required to reconstruct the original seed phrase. This means that you could give one share to each of three different trusted friends, and as long as any three of them are able to get together and combine their shares, they will be able to recover the original seed phrase and access your bitcoin wallet. This can be a more secure way to back up your seed phrase because it reduces the risk of a single point of failure. If you were to just give a copy of your seed phrase to one friend, and something were to happen to that friend or their copy of the seed phrase, your wallet would be at risk of being lost forever. But with Shamir's secret sharing, as long as any three of your five friends still have their shares, you can recover your wallet. --- # 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 dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.allforone.app/glossary/definitions/self-custody-wallets/shamirs-secret-sharing.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. 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.