> For the complete documentation index, see [llms.txt](https://docs.ethsign.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ethsign.xyz/a-deeper-dive/technical-details/signature-verification.md). # Signature Verification The ability to independently verify the validity of a digital signature is just as important as the act of signing, and this is exactly what EthSign Signatures offers. To verify your downloaded PDF file online, head [here](https://app.ethsign.xyz/verify). ## EthSign Certified All documents that have completed signing are settled on Arweave. Since our document data structure is public and Arweave is an open network, technically anyone can upload data and have it considered "valid" as long as they conform to our data structure. This is not something we condemn — in fact, our game plan is to build a protocol and we love it when others build on top of our standard. However, sometimes it is still necessary to distinguish an official implementation from a third-party implementation. This is the idea behind the "**EthSign Certified**" stamp - all documents created and signed on the official EthSign platform are [digitally signed](https://docs.ethers.org/v5/api/signer/#Signer-signMessage) by a private key that EthSign controls and can be [independently verified](https://docs.ethers.org/v5/api/utils/signing-key/#utils-verifyMessage) offline. We also attest all [document signing actions](https://scan.sign.global/schema/SPS_blSzPTC9SIL9HS52PZXST) and [completions](https://scan.sign.global/schema/SPS_vpnl9gIq-mqOXlBYQMsqf) on [Sign Protocol](https://sign.global). * EthSign Certified signing address (attest.ethsign.eth): `0x91f0ff8089A78A135E11123D84c07F9D93883E79` ## Verification Page Users can verify the integrity of the original contents of their completed and downloaded PDF against the Arweave copy and the digital signatures within said downloaded PDF on our [verification page](https://app.ethsign.xyz/verify). --- # 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.ethsign.xyz/a-deeper-dive/technical-details/signature-verification.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.