Five Blockchain Startups Using Token-Curated Registries

A look at MetaX, District0x, Messari, Ocean Protocol and MedCredits

Token-curated registries are similar in some ways to previous kinds of business registries

Token-curated registries (TCRs) are blockchain-based lists that are managed by members through a voting mechanism. They are usually incorporated into larger token-based networks, but they can also stand alone. This article will look at five crypto startups that have TCRs under development as part of their networks: MetaX, District0x, Messari, Ocean Protocol and MedCredits.

How Token-Curated Registries Work

Mike Goldin of ConsenSys wrote a piece last year that laid out the basics of TCRs. According to Goldin, there are three user types in a TCR: consumers, candidates and token holders. He wrote: “Consumers desire high-quality lists. Candidates desire to be included in such lists. Token holders desire to increase the price of the tokens they hold.”

Here is how it’s intended to work: If the quality of the members of the TCR is high, then consumers will be interested in it and outside parties will want to become members. This will create demand for the tokens that the TCR has issued and lead to an increase in their value. Current members, who hold tokens, would be thus incentivized to allow only high-quality members join.

If a candidate wants to join a TCR, they must pay an application fee denominated in the TCR’s token. Put another way, the candidate must put a stake into the TCR before joining, like how players joining a card game must buy chips. If an existing member wants to stop the candidate from joining, they can challenge. A blockchain-managed vote would be held, with one token being equal to one vote. (In many of the current TCR projects, Ethereum is being used.) Thus, members holding more tokens would have a greater influence on the outcome.

If the candidate is accepted as a member, then they will keep their deposit and be able to transact with consumers on the network. If, however, the candidate’s application is rejected, then her deposit is forfeited and divided up among the list members who voted against her. A member can withdraw her deposit and leave the TCR at any time.

That is, in a nutshell, how token-curated registries work. Now, here’s a look at the five projects that are using TCRs in their crypto network.


MetaX is creating an Ethereum-based blockchain called adChain which allows advertisers to find trustworthy publishers and provides parties with a platform for tracking advertising impressions. In their white paper, the company claims that their system is more transparent than existing ad networks and better at preventing fraud.

The first protocol under development for adChain is a TCR which lists trustworthy, non-fraudulent publishers for advertisers to place their ads. The quality of the registry won’t be verified by MetaX in any way; instead it will be managed by the publishers themselves following the conventions of a TCR.

The token used by adChain is Adtoken (ADT). A token sale took place in June of 2017, which raised $10 million USD. 1,000,000,000 ADT were issued. The adChain network is scheduled to be live on the Ethereum mainnet in April 2018. MetaX is working with Ethereum developer ConsenSys to build the platform.


District0x allows for the creation decentralized marketplaces and community applications, which they call districts. District0x runs on the Aragon network and IPFS. The first district launched was Ethlance, a freelance online job board focusing on Ethereum, in early 2017. Since then, they have created another district called Name Bazaar, which allows for the buying on domain names on the Ethereum Name Service. They have plans for another district called the Memefactory, which will allow users to “create and trade provably rare digital assets on the Ethereum blockchain.”

District0x incorporates TCRs in the form of the District Registry, which according to the white paper, is “decentrally maintained district whitelist, storing the credentials of districts which have been granted access to the district0x Network.” When a district is part of the District Registry, it shows that the district has been accredited by token holders as non-malicious and valuable addition to the district0x Network.

District0x explicitly states on their blog that the District Registry was based on the adChain model:

The District Registry is modeled after the adChain Registry, a collaborative effort between ConsenSys and MetaX, which makes use of a deposit and challenge mechanism to allow token holders to maintain a whitelist of approved members in a decentralized manner.

However, the District0x system has a slight variation, as it will not have a 1:1 ratio of tokens to votes. Instead there will be a sliding price curve that favors early supporters of the district (see the white paper, page 14).

District0X held a token sale in the summer of 2017 for their District0x Network Tokens (DNT) which raised $9 million USD. 1,000,000,000 district0x Network Tokens were issued, with 60% going to participants in the first round of the token sale, 20% going to founders, 1.5% going to advistors, 0.5% going to early contributors and the remaining 18% in reserve.

In a recent blogpost, District0x said it plans to launch Memefactory at the same time the Aragon Core app is ready to deploy on the Ethereum mainnet. This will happen with the release of Aragon Core v0.5 (confirmed in this update video, minute 21:00). Previously, the company had committed to releasing Aragon Core v0.5 in February 2018, but this didn’t happen. According to Aragon, this will now be occurring in early March.


Messari is a new venture from crypto entrepreneur Ryan Selkis (also known as TwoBitIdiot) which intends to create an industry list of reputable crypto projects. Due to its global nature, government regulation of the crypto space is currently patchwork and under the authority of various countries, provinces and states. In a lengthy blogpost, Selkis noted that CFTC member Brian Quintenz recently called for the industry to consider forming a self-regulatory organization. Since crypto projects are naturally decentralized and thus self-governing, Selkis sees the opportunity for organizing this group as token-curated registry.

As with other TCRs, a list would be created featuring high-quality, legitimate crypto projects. These initial members of the TCR would then control who could join by the voting system outline above. If successful, Selkis sees Messari as a way for the crypto industry to police itself and minimize the amount of regulations imposed by governments on the crypto industry.

The project was just announced at the beginning of March, so the project is still in its incipient phase and there has no been plans for an ICO revealed nor further financial details.

UPDATE 7 March: Messari has announced the closing of a seed round of funding from multiple investors.

Ocean Protocol

Ocean Protocol is a proposed decentralized platform to allow for marketplaces of the kind of big data used for artificial intelligence systems. With Ocean, consumers and providers will be able to buy and sell data that could be used in autonomous vehicles, medical research or other applications which require large amounts of data.

The TCR aspect of the plan manages access to the Ocean network for parties such as data and network service providers. The scheme is the same as other TCRs, with one variation, according to the white paper. In the Ocean Protocol, there is something called risk-staking, where prospective members can have current members vouch for them. Under this setup, a current member puts their token deposit at risk on behalf of the new member. In return, the current member gets a share of some of the token earnings from the new member. All the other mechanisms of the TCR work essentially the same as other systems like adChain.

The Ocean Protocol Foundation is based in Singapore. A company called BigchainDB will develop the protocol and network for Ocean Protocol. Another company called DEX is building the marketplace framework. The ICO date is 7th March. Total supply of Ocean Tokens will be 1.41 billion. The network should be launched the first quarter of 2019. The public Pre-Launch target raise is €9M / $11M for 3.2% of the token supply. The distribution will be 45% keepers, 25% acquirors, 20% founders, 10% to the Foundation.


U.S.-based MedCredits plans to be a Ethereum-based platform which will allow patients and doctors to connect using a decentralized network. MedCredits plans to act as a physician registry, electronic health records system and marketplace. At their initial launch, they will create a TCR which will be a list of dermatologists that consumers can contact directly for medical services. They have five U.S. medical doctors on their team and are being advised by Tim Enneking of Crypto Asset Management.

According to the white paper, 100 million MedCredits (MEDX) will be issued in an ICO planned for March or April of 2018. 70% will be available for token sale participants, 20% percent will go to the MedCredits team and 10% will be held in escrow for partnerships and incentivizing physicians. They are currently accepting registrations for the pre-sale, which is not open to U.S. contributions.


The use of token-curated registries has caught on since its initial conceptualization. While the idea has yet to be tested at large scale over time, many crypto entrepreneurs think the idea has merit. And with the launch of many new crypto networks in 2018 that are incorporating TCRs, investors will soon have a better idea of their utility.