Introducing, Non-Transferable Tokens (NTTs)

We’ve been in touch with various developers and projects since launching Simple Assets last February, and after repeated requests, we’ve added Non-Transferable Tokens to Simple Assets.


Simple Assets is an opensource standard for digital assets on EOSIO blockchains. It was recently made the default NFT standard on WAX, which supports an enormous marketplace for virtual goods.

Simple Assets supports Non-Fungile Tokens, Fungible Tokens, and now . . . Non-Transferable Tokens. (see Change Log v1.2.0)

Why Digital Assets?

There are several reasons why a developer may want to use a digital asset standard:

  1. A lot of functionality is already developed, and edge cases worked out, saving hundreds of hours of work.
  2. So that users can express their ownership of digital assets in a decentralized way, even outside the control of the Dapp that created them.
  3. So that a user’s assets show up in third party asset explorers and can be traded in third party asset marketplaces (like

Why NTTs?

Non-Transferable Tokens have been requested by a few different developers and projects who are integrating Simple Assets, predominantly for two reasons:

  • To give awards and trophies.
  • To grant official certificates or licenses.

What’s the point?
We were a little surprised by these requests. The main point of digital assets is to be able to transfer them. Without transfer functionality, we mistakenly thought, the trophies or certificates would be better expressed in the internal logic of the Dapp.

It turns out that there are two benefits:

  • Ready, easy-to-use logic for creating and updating digital objects.
  • The Assets, though non-transferable, will be displayed in third party asset explorers.

Why not use NFTs?
We briefly considered sticking only with NFTs.

Trophies and awards might have the winners data etched onto them, but still be tradable.

Certificates and licenses would also remain tradable, but they would maybe have to be registered with some authority in order to be active.

However these work-arounds seemed conceptually awkward. Enough people wanted the simplicity of unique non-transferrable tokens.

Lastly, Why not add a freeze feature to NFTs?
We considered adding a flag to NFTs that makes them non-transferable, and looked closely at this because other NFT standards have this feature.

Technically, it makes a lot of sense, since NTT’s pretty much encompass all the functionality of NFTs, minus the transfer-related functionality. However, we ultimately decided that the conceptual distinction is important enough that they warrant their own name.

Simple Assets is a single contract, but it has different actions for NFTs, FTs, and now, NTTs, and it stores each of them in separate tables.

A new name for a new concept.

The whole point of putting digital assets on a blockchain is to separate their functionality within some dapp from their ownership. Ownership should be as pure and decentralized as possible, and beholden to no centralized authority — not even the smart contract which created them. We think that making NFTs sometimes transferable and sometimes not, muddles the pure expression of ownership which we strive to achieve with Simple Asset NFTs.

NTTs are a distinct form type of property, operating under different rules, and deserve their own vocabulary.


CryptoLions is an EOS Block Producer based in Ukraine. We strive to make EOS more valuable by building projects that improve the ecosystem, by setting the standard for transparency and accountability, and by popularizing EOS all over the world.