Bitcoin Forum

I am looking for a service or tutorial that instructs on how to use the timestamping feature of the blockchain to record the existence and immutability of important documents.

We want to timestamp a document into the blockchain for a "proof of existence". It is also useful that the block will demonstrate the time it was created.

Does anyone on this board have a recommendation about which service to use or how to do this? It is preferable not to use a 3rd party.

I have downloaded the blockchain but am not particularly inclined to start running a full-node.

Thank you for any and all help.

Here are two timestamping services ^{[I'm not vouching for them]}:

• Bitcoin.com Notary (https://notary.bitcoin.com/)
  ^{- An old service but never tried using them.}
• STAMPD (https://stampd.io/)
  ^{- Found their service from googling.}

---

Tutorial:

• Notarization in Blockchain
  - Part 1 (https://medium.com/@kctheservant/notarization-in-blockchain-part-1-a9795f19e28d)
  - Part 2 (https://medium.com/@kctheservant/notarization-in-blockchain-part-2-1a06d00eb72)
  - Part 3 (https://medium.com/@kctheservant/notarization-in-blockchain-part-3-ce176c1ac338)

Since this is in Bitcoin I am somewhat hesitating to refer to FLO (https://bitcointalk.org/index.php?topic=236742) (Florincoin), but nonetheless it could be relevant depending on your requirements regarding security and space for notarizations.

FLO obviously doesn't offer the level of security that BTC has due to much lower hashrate, but it allows you to store up to 1024 bytes of flodata per tx directly and easily from the wallet.

HTH

Or you can use Scrypta blockchain
https://medium.com/@scryptachain/scrypta-blockchain-functioning-examples-a9937a34a354

Through the mobile app, you can already upload, enrcypt and save your files over blockchain
Any file will be provided by proof-of-existence, and the service cost only 0,0002$ in Lyra
For more info join our discord server https://discord.me/scryptachain (https://discord.me/scryptachain)

Any kind of service outside from your organization/subsidiary will always count as a 3rd party service so I doubt that I can recommend you anything aside from developing your own blockchain for the purposes of time stamping  your documents. This is the only way to know that the blockchain you have is not tainted with any kind of dirt as you are the one who developed and control it and you are the only one who has the access for it. Maybe what you are looking for instead is a developer who can do develop your own blockchain-based time stamping program.

You could hash the document and then put the hash on a tx output. That's literally what you should do, no need for fancy stuff or jargon like machine learning timestamping.

The block will always have the details of when it was created so it should be no problem.

Our solution is totally decentralized and our codes are totally opensourced
https://github.com/scryptachain

it's not necessary to create your own blockchain, just download Manent app
https://manent.app/en/ (https://manent.app/en/)

That is a bad idea, you do know that he will be able to manipulate the data whenever he wishes right? Centralized blockchain is just another database which can be mutated whenever the company wishes...  It just saves them the trouble of syncing the data across multiple servers... Wouldn't recommend.

@Paleus follow what @joniboini has suggested it's the best way IMO. Check this thread out on to do it: https://www.reddit.com/r/btc/comments/49pp3n/eli5_how_to_embed_text_into_a_bitcoin_transaction/

There is a website called: https://www.proofofexistence.com which does exactly what you are looking for but you can do it for free by reading the thread I linked above.

If you want to timestamp documents yourself, without needing to use a third-party service, you can use the OP_RETURN opcode to create an invalid transaction, & put ~40 bytes of arbitrary data into the scriptPubKey of a transaction output. You can either store a (small!) hash in there, some UTF8 encoding, or similar, referencing your document. Then you have a record in the blockchain (although certain nodes will prune it upon seeing the OP_RETURN opcode) of your message, timestamped.

a transaction that has an OP_RETURN output is not invalid, that particular output is not spendable (for obvious reasons) that is why the amount of it is set to zero otherwise you would be burning coins.
as for the size the 40 byte is a very old rule, nowadays the limit is 83 bytes.

Hi,

You could have a look at https://www.bytestamp.net/ - it is a free tool to timestamp & produce proof of existence of anything.

If you want to do it your self, have a look at https://bitcointalk.org/index.php?topic=2188160.msg50735129#msg50735129 - this is done using Datacoin.

Hope it will put you on the right track.

H