Pettit is removed from the prior-art ledger

Maintainer ruling: it was not really used. The entry recorded an idea — that holding-responsible is a relation between parties rather than a property of one — without an identified work, and the maintainer confirms no source was read for it. It is removed from the conceptual-dependency list rather than left marked unpinned, because an entry nobody used is not a dependency with a missing citation; it is not a dependency.

The record of the correction stays, so the ledger shows the entry was examined and dropped rather than silently vanishing. Where the two-place shape of answerability needs an antecedent, Brandom's scorekeeping is the one the program actually uses, and wiki/Sources.md separately cites Fischer & Ravizza for reasons-responsive mechanisms.

Rejected alternative: keeping it marked exact source not yet pinned. That is the right marking for an idea in use whose source is lost, and the wrong one for an idea that was never taken.