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Does this mean that you need to constantly renew electronic seals in electronic documents or signatures with their certificates? There’s no sense in doing that. How could a company renew its stamp on all the digital originals of a document that no longer exists? Or, similarly, the signature of a person who has since passed away? If you need strong certainty that no-one has changed a document, you need to furnish that document (or set of documents (!)) with a continuous series of currently-valid timestamps.
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Ensuring a document or set of documents is unchanged using a series of timestamps
The furnishing of timestamps for documents or sets of documents is provided by what are called “trustworthy archives.” Signi will be one provider of such archives, and companies can likewise store documents from Signi in their own archives, to which they also send other documents – for example issued invoices that no-one is signing. Whether or not to use an archive, and for what documents or sets of documents to use it, meanwhile, is a choice for every company, similar to the decision between keeping documents in binders at the office, in a safe, or in a professional paper archive.
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