Wash Trading Flags

Our Wash Trading Flags are designed to detect wash trading activities on NFT marketplaces.

Approach

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

We use various heuristics to flag potential wash trades, assign a score to each heuristic, and then compute 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.

Sample Query

Get a breakdown of NFT wash trading levels across all chains

select
    date(block_timestamp) as date,
    chain,
    wash_trading_level,
    sum(usd_amount) as usd_volume
from crosschain.nfts.trades_with_wash_trading_flags
where block_timestamp >= current_timestamp - interval '30 days'
group by all

Get a granular, transaction-level breakdown of wash trading details incl. the funding wallets of traders, and the pattern of wash trading detected. These details can also be used to compute custom wash trading metrics.

select
    chain,
    block_timestamp,
    transaction_hash,
    wash_trading_score,
    wash_trading_level,
    extra_fields:wash_trading_details as wash_trading_details,
    extra_fields:wash_trading_details:wash_trading_flags as wash_trading_flags,
    extra_fields:wash_trading_details:buyer_birth_funding_wallets as buyer_birth_funding_wallets,
    extra_fields:wash_trading_details:seller_birth_funding_wallets as seller_birth_funding_wallets
from crosschain.nfts.trades_with_wash_trading_flags
where block_timestamp >= current_timestamp - interval '1 days'

Wash Trading Flags

Wash Trading Flags	Weighting	Description	Scope
buyer_is_seller	4	the buyer address is the same as the seller address	EVMBitcoinSolana
instant_refund	4	the majority of the purchase price of an NFT is returned by the seller, in the same transaction, to the buyer, or to the wallet that funded the buyer in the same transaction. Commonly occurs with flash loans.	EVM
traders_first_funded_each_other	3	one of the buyer’s first funders is the seller, and one of the seller’s first funders is the buyer	EVMBitcoinSolana
back_and_forth_token	2	the same NFT is traded between the same seller and buyer, within a specified time window	EVMBitcoinSolana
back_and_forth_collection	1	NFTs from the same collection are sold back and forth between the same seller and buyer, within a specified time window	EVMBitcoinSolana
buyer_funded_seller_recently	1	buyer funded seller within a specified time window from the point of a transaction	EVMBitcoinSolana
seller_funded_buyer_recently	1	seller funded buyer within a specified time window from the point of a transaction	EVMBitcoinSolana
same_nft_traded	1	an address buys or sells the same NFT within a specified time window, an excessive number of times	EVM (ERC-721 only)BitcoinSolana
same_first_native_funder	0.5	buyer and seller share at least one overlapping first funder address	EVMBitcoinSolana
same_most_frequent_native_funder	0.25	buyer and seller share at least one overlapping most frequent funder (based on funding transaction counts)	EVMSolana
trade_transfer_trade_again	0.25	NFTs are traded, transferred and traded again between the same seller and buyer, within a specified time window	EVM (ERC-721 only)BitcoinSolana

Wash Trading Level

wash_trading_level - The Wash Trading Level is derived from the Wash Trading Score, and 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