Introduction

I tried to learn from an NFT influencer on twitter on analysing what NFT projects that this person bought / minted. After a few days, I saw him minted lots of tokens on a project, and I was almost certain to follow him and minted the same tokens.

As I am a geek person, I love looking at etherscan.io and realised that this token I was about to buy looks weird. It is an ERC-721 smart contract, but it has 0 max supply. Then when I looked at holders list, I was almost certain this project is “real” based on the holders ENS names there.

“Official” website said that total sale is 700 tokens, and total quantity of top 50 holders are more than 700 tokens. Let’s deep dive on why I think this project and a few more similar projects are possible scam projects.

What is a Non-Fungible Token?

A Non-Fungible Token (NFT) is used to identify something or someone in a unique way. This type of Token is perfect to be used on platforms that offer collectible items, access keys, lottery tickets, numbered seats for concerts and sports matches, etc. This special type of Token has amazing possibilities so it deserves a proper Standard, the ERC-721 came to solve that!

What is ERC-721?

The ERC-721 introduces a standard for NFT, in other words, this type of Token is unique and can have different value than another Token from the same Smart Contract, maybe due to its age, rarity or even something else like its visual. Wait, visual?

Yes! All NFTs have a uint256 variable called tokenId, so for any ERC-721 Contract, the pair contract address, uint256 tokenId must be globally unique. That said, a dApp can have a "converter" that uses the tokenId as input and outputs an image of something cool, like zombies, weapons, skills or amazing kitties!

https://ethereum.org/en/developers/docs/standards/tokens/erc-721/

Deep dive on Top 5 NFT tokens

Let’s have a look at top 5 tokens on Etherscan as at 22/01/2022 3pm AEST. I will compare Max Total Supply and find out who owns token #1.

Reptile Armoury

Contract address: 0x5f4a54E29ccb8a02CDF7D7BFa8a0999A8330CCeD

Owner of Token #1

Flipped Doodles

Contract address: 0xaa74955674127e98e6ce30f65b676f18c5176f7b

Owner of Token #1

Flipped Punks

Contract address: 0x7dafe71db8cf7edb682e762529c8af78fed569c5

Owner of Token #1

Bored Ape Flipped Club

Contract address: 0x99f979526346cb20b07df858e6e592cfd6f48276

Owner of Token #1

Dead Army Skeleton Klub

Contract address: 0x19d84B2A4B21910339aF097A1bDdB48682D6F47d

Owner of Token #1

Summary

Based on ERC-721 standard, each token id on contract must be globally unique. From top 5 NFT tokens, only Reptile Armoury and Dead Army Skeleton Klub that follow ERC-721 standard. Token #1 only has 1 owner.

Flipped Doodles, Flipped Punks and Bored Ape Flipped Club don’t follow ERC-721 standard. Each token id is NOT unique and on contract there’s no max supply.

In my opinion, those 3 projects may be scam projects due to violation of ERC-721 standard. If those contracts were deployed under ERC-1155, it would be a different story. As a geek person, I would avoid those 3 NFT projects.

Please be careful before buying an NFT, and always check contract details on Etherscan.