A TCR that decentralizes token listing on DEXs

User experience on The Token Registry

In the development of nascent technologies, protocol design breakthroughs can often be applied broadly. This is certainly the case in the recent explosion of decentralized ecosystems. While a particular development may be designed with a specific use-case in mind, the fundamental game theory, incentive scheme and protocol is likely widely applicable.

One contemporary example is SpankChain’s state channels. While originally launched in 2015 as a payment system for adult content, SpankChain’s state channels have been widely praised as a potential solution to increasing throughput and decreasing gas costs in the Ethereum ecosystem.

For us, what started out as a Token Curated Registry (TCR) of physicians, has evolved into an entirely new TCR design for curating any list of objective content.

The MedX TCR was designed for the purpose of creating a decentrally maintained, global network of physicians where verifiers worldwide reviewed physician credentials for admission to the registry. This network of physicians could then be instantly accessed for free by any healthcare or telemedicine application (more details can be found here). This TCR design, however, can be used for a multitude of other applications. Specifically, I’d like to discuss the potential utility of our TCR in decentralizing the token listing process for decentralized exchanges (“DEXs”).

One step closer to fully decentralizing DEXs

Since the public release of the SEC report on EtherDelta, DEXs fell under public scrutiny when it became apparent that decentralized exchanges are, in many ways, actually centralized.

Today, nearly all DEXs have a centralized token listing process whereby exchange owners manually list tokens. Even for DEXs with public/open token listings, the exchange owners manually mark or rank the legitimate tokens so that traders can avoid confusion with undesirable tokens. This process is carefully monitored to ensure that the listed or “verified” tokens have correct contract owner addresses, ticker symbols and logos to prevent any confusion or costly mistakes by traders. This information is currently maintained by exchange owners, MetaMask personnel and other centralized third parties.

This process can actually be quite burdensome, as stated by the MetaMask team in the MetaMask GitHub under Submission Process.

“Maintaining this list is a considerable chore, and it is not our highest priority. We do not guarantee inclusion in this list on any urgent timeline. We are actively looking for fair and safe ways to maintain a list like this in a decentralized way, because maintaining it is a large and security-delicate task.”

We believe that our TCR could be the decentralized solution that the MetaMask team describes.

The Token Registry for DEXs

We propose The Token Registry as a decentrally curated list of verified ERC-20 tokens. The output of this registry is a list of tokens with the following curated information:

  • One unique name/ticker symbol per token
  • One contract owner address per token
The REP token listing is being challenged (submitted contract address is incorrect)

With this verified information, traders on exchanges need not worry about being accidentally or intentionally spoofed into buying undesirable or fraudulent assets. Moreover, by requiring a fee and deposit to register a token on The Token Registry, the registration of spam tokens will be minimized.

Submit any ERC-20 token registration in minutes

The Token Registry is now available for testing on the Ropsten Testnet at https://tokenregistry.medxprotocol.com. With app-native faucets and an easy UI, users can begin registering tokens and verifying submissions in minutes (as shown below).

In-app faucet to quickly obtain testnet TEX/ETH tokens
Registry token listing homepage
Stake a deposit in TEX to submit a token for entry in the registry
Stake TEX and earn rewards by verifying token submissions

After a brief period of bug fixes, we aim to deploy The Token Registry on Ethereum mainnet in early Q1 2019. As the list of registered tokens grows, we foresee this as an affordable and expedient option for exchanges to decentralize the token listing process.

How does The Token Registry relate to MedX?

Over the past year, we set out to develop a TCR of physicians. After carefully studying and testing the existing TCR models, we concluded that the incentive structure of these TCRs could be improved for the curation of lists of objective information. This is expounded on in greater detail in Dr. Praver’s article on Subjective vs Objective TCRs. In brief though, the incentive structure for the adChain TCR model is dependent on disagreements between token-holders in verifying subjective content (e.g. America’s best colleges, New York’s worst restaurants). In the curation of objective content, however, there is rarely disagreement and, in turn, rarely rewards for curating content. This is a problem for decentralized platforms that use the adChain TCR for curating objective content. Despite this challenge, most existing TCRs are still based off the adChain design, which is detailed further in Mike Goldin’s seminal blog post.

For the MedX Protocol, we needed a TCR that properly incentivized verifiers of objective content — physician credentials. This required an entirely new TCR design whereby verifiers are properly incentivized to perform quality work even if there is little friction or disagreement with other token holders/verifiers.

From the ground up with entirely new smart contracts and user interface, we built a new TCR model for objective content.

Stay tuned next week when Dr. Praver and our development team will publicly release a detailed description and parameters of our TCR protocol!


The Token Registry could be useful for taking DEXs one step closer toward, well, decentralization. By implementing a decentralized token listing process that is trader-friendly, DEXs would no longer be responsible for manually listing or verifying new tokens.

Lastly, The Token Registry will serve as a great way to test our new TCR protocol before launching the MedX physician TCR on Ethereum mainnet. This is critical to avoid a situation where potentially fraudulent, non-credentialed physicians could enter the MedX Health System.