The most dangerous signing failure can preserve the appearance of procedure.
Why it matters
The incident shows why multisignature counts do not help when signers approve a deceptive interpretation of the transaction.
Known
The FBI published its attribution and approximate loss. Bybit described the affected signing path and said the compromise did not represent a broad breach of its exchange infrastructure.
Operator account versus independent record
The operator's technical account is material but interested evidence. Government attribution answers a different question and can also evolve; the two sources should not be collapsed into one voice.
Trust boundary
The boundary included signer devices, displayed transaction meaning, front-end and dependency integrity, approval policy and the ability to halt or contain movement after detection.
Durable lesson
High-value signing needs independent decoding, destination allowlists, human-readable intent, separation of preparation from approval, and drills for emergency containment. This is defensive architecture, not an exploitation recipe.