> ## Documentation Index
> Fetch the complete documentation index at: https://docs.allium.so/llms.txt
> Use this file to discover all available pages before exploring further.

# Wash Trading Flag

Our Wash Trading Flag is designed to detect wash trading activities on NFT marketplaces.

## Approach

Wash trading can be inferred through on-chain movement of NFTs and funding patterns across different buyers and sellers of NFTs.

In our mode, we considers multiple factors as input factors, assigns a score to each factor, and then computes a wash trading score based on the sum of these factors.

The output is then classified into different levels of wash trading ranging from `very low` to `very high`. The Wash Trading Flag is customizable, and users can query extra columns to have a more granular view.

### Sample Query

Finding overall wash trading levels on Ethereum NFT marketplace.

```sql theme={null}
select 
    date_trunc('week', block_timestamp) as date,
    wash_trading_level, 
    sum(usd_price) as usd_volume
    from ethereum.nfts.trades_with_wash_trading_flags
where block_timestamp > '2022-01-01'
group by 1,2 
order by 1
```

<Frame>
  <img src="https://mintcdn.com/allium-e770e2b7/M3SuvBIUs-0g-3vo/images/image-historical-evm-ethereum-nfts-wash-trading.png?fit=max&auto=format&n=M3SuvBIUs-0g-3vo&q=85&s=37e42200f93bc9859c64aea7746cf9c8" width="790" height="445" data-path="images/image-historical-evm-ethereum-nfts-wash-trading.png" />
</Frame>

<Card href="https://app.hex.tech/fc6e427a-6bfb-40e5-9cc1-1808967c3c12/app/fd5def55-063a-433f-83f6-26d01f9e15f2/latest?selectedStaticCellId=46235781-50d5-474d-9a4e-81ccabb3530f">
  Output of the query above.
</Card>

## Input Parameters

The Wash Trading Filter takes the following input parameters:

**Wallet Funding Patterns**

* `buyer_birth_funding_wallet`: address that first sent an ERC20/ETH to the buyer

* `seller_birth_funding_wallet`: address that first sent an ERC20/ETH to the seller

* `wallets_first_funded_each_other`: true if the buyer funded the seller or vice-versa

* `wallets_first_funded_by_same_wallet`: true if the same wallet funded both buyer and seller (excluding the top 500 CEX addresses)

**NFT Trading Patterns**

* `nft_traded_back_n_forth`: true if the same NFT was traded by the buyer and seller multiple times

* `buyer_address_equals_seller_address`: true if the buyer and seller are the same

* `buyer_traded_same_nft_multiple_times`: true if the buyer traded the same NFT more than once in a window of +-7 days since the given trade

* `count_same_nft_trades_by_buyer`: number of times the buyer traded the NFT (except for the first time) in a window of +-7 days since the given trade

* `seller_traded_same_nft_multiple_times`: true if the seller traded the same nft more than once in a window of +-7 days since the given trade

* `count_same_nft_trades_by_seller`: number of times the buyer traded the nftNFT(except for the first time) in a window of +-7 days since the given trade

* `seller_funded_buyer_recently`: true if the buyer sent ERC20s/ETH to the seller 24h before or after the trade

* `buyer_bought_same_nft_from_seller`: true if the buyer bought the same NFT from the seller multiple times

## Output Parameters:

### Wash Trading Score

The Wash Trading Filter outputs the following:

`wash_trading_score` - The Wash Trading Score is computed by adding up the scores of each input parameter as follows:

* `wallets_first_funded_each_other` \* 3

* `wallets_first_funded_by_same_wallet` \* 0.5

* `nft_traded_back_n_forth` \* 1.5

* `buyer_address_equals_seller_address` \* 3

* `iff(token_standard = 'ERC721', buyer_traded_same_nft_multiple_times, 0)`

* `iff(token_standard = 'ERC721', seller_traded_same_nft_multiple_times, 0)`

* `seller_funded_buyer_recently`

* `iff(token_standard = 'ERC721', buyer_bought_same_nft_from_seller::int, 0.25)`

### Wash Trading Level

`wash_trading_level` - The Wash Trading Level is derived from the Wash Trading Score, and it is classified into different levels as follows:

* 'very low' if wash\_trading\_score = 0

* 'low' if wash\_trading\_score \<= 2

* 'medium' if wash\_trading\_score \< 3

* 'high' if wash\_trading\_score \<= 4

* 'very high' if wash\_trading\_score > 4