A retroactive airdrop rewards people who used a product before its token existed, with no advance announcement and no form to fill in.

Projects use snapshots of past blockchain activity to decide eligibility, often tiered by how early, how active, and how varied a user's history was.

Sybil filters exclude bot-like patterns such as identical transactions across dozens of wallets, which is why genuine, varied usage is rewarded over industrial farming.

Beware of anyone selling guaranteed allocations or whitelist spots: real retroactive airdrops are announced only when the claim opens.

Position yourself by using products you genuinely like, trying new features early, and keeping records for tax purposes, since airdropped tokens are taxable in many countries.