Flagged Tokens

Reservoir offers a range of APIs to help developers to track and exclude NFTs that are flagged on OpenSea:

View the "non-flagged" collection floor price (on-demand or historical)
Show a list of Tokens, with flagged tokens filtered or indicated
Fetch all Token IDs in a collection that are flagged
Exclude flagged tokens when placing collection offers
View changes in flag status, to keep your own DB in sync
Oracle for excluding flagged tokens in on-chain applications

Relevant Fields

isFlagged = whether or not the token is flagged (0 or 1)
lastFlagChange = date that the flag status last changed
lastFlagUpdate = date that the flag status was last checked

Freshness

We strive to have the freshest possible data using the following methods:

Automated re-checks popular collections and floor tokens
Crowd-sourced re-checks from users of the Reservoir SDK, as they view tokens

That said, there is always a risk of us not being perfectly in sync. If you only need data for a single token, it is always safer to check OpenSea directly. In fact, there is a method in the Reservoir SDK that makes this easy to add to your app, and report back to our API if it notices a discrepancy, crowd-sourcing better results for everyone.

Non-Tradeable Tokens

The strict definition of a "flagged" token is that it is "not tradeable on OpenSea". Unfortunately, there are other reasons that a token might not be tradeable, other than being reported stolen, and it's not possible to differentiate these. For example:

NFTs that pre-date ERC-721 (e.g. CryptoPunks)
Tokens that can be staked without lockup (e.g. Moonbirds & The Potatoez)

For these collections, all tokens or a large number of tokens will be marked as "flagged". We are actively working on a potential solution, but don't have one yet.