UNUS SED LEO token audited.


This article is intended to explain the details of LEO token implementation from a technical and security point of view, the safety of using this token, as well as answer frequent questions related to this smart-contract and smart-contracts in general.

A couple of words about me

I am Dexaran, a pseudonymous crypto decentralist and developer. My main speciality is information security. I am the founder of Ethereum Commonwealth, the co-founder of Callisto Network and the creator of ERC223 token standard.

LEO token contract audit

Callisto Network recently audited the LEO smart-contract. You can review the final report here. I can conclude that the token is secure from the technical side.

Two LEO contracts (ERC20 and EOS)

The first thing that must be said is that LEO token is deployed on two chains — Ethereum (ERC20 contract) and EOS (EOS LEO contract).

Token related issues

Many have heard of the ERC20 standard, but not everyone is aware of its problems. The problem here is that the ERC20 token standard is insecure by default and it may cause monetary losses for investors. I wrote several articles about these problems already.

Real threats in smart-contracts

The lack of upgradeability or owner control features is a threat in case of smart-contracts.

Misunderstanding the conception of smart-contracts


I would call LEO token one of the most secure smart-contracts in the whole Ethereum ecosystem. It is one of the few ERC20 tokens that is not prone to the common critical problems of the ERC20 standard.