How do digital signatures work in Estonia and how can they work for NFTs?

After an attempted discreet launch of our project Sinelock, we have had a lot of questions regarding how this works. So here is a short explainer on how digital signatures can be used to sign a contract for the ownership of a non-fungible token.


Firstly anyone could make an NFT, for example a picture of the Sinelock logo. If you were new to the NFT space, perhaps one of the most simple ways of minting this would be using Rarible.

So as you can see here, we have uploaded an image and we will then go on to write a little description and then mint the token.

The token is then visible on Rari, and in this case we decided to then just simply use Rari to transfer it to another address. Now in the world of NFTs we would consider this a very normal way to send an NFT from one person to another. You can view this token here, it now has an owner which is not Groovy.

In this case the token has no value, but what if we used an NFT to transfer ownership of an expensive painting which is redeemable. You may have transferred it to another address but is there a legally binding contract to say the ‘owner’ now indeed has it? No, it simply exists on the blockchain in a different wallet. The Sinelock team see no problem with this for most digital NFTs, but we have sold plenty of redeemable records with Groovy. So how can you ensure real ownership? We think using ID cards and digital signatures is the answer.

So, we can mock up a contract, here is a simple pseudo-contract as an explainer (the Sinelock program will have templates for you to use drawn up by lawyers).

We then insert our ID card into our laptop.

We then can sign this contract using our ID card and our passwords.

We have done this using the Estonian program Digidoc, we now export this as an ASICe file, and if we send it to the new owner they have a signed contract that we have transferred ownership. Sinelock will do all of this in a streamlined manner and enable interoperability between multiple ID cards across Europe. We will begin with Estonia, Finland and Iceland before then slowly adding more nation states.

We hope this explains what our platform will enable you to do.

All the best.


A platform for redeemable NFTs as vinyl records.