sdd:Suppression
A sdd:Suppression is the record minted by the % operator: %node/`%edge` for a whole-instance suppression, or <primitive> <path> %"old" for a lone datum value with no replacement. It says "this exists per our intent, and we explicitly exclude it" — not "this doesn't exist." A whole-node suppression, a whole-edge suppression, and a lone-value suppression each mint their own sdd:Suppression instance directly on the suppressed stanza's own skolem — a node's, an edge's, or a datum's — never a separate record node addressed some other way.
Its sdd:parent is the owning group or scope. For a suppressed node, sdd:subject names the node's own depicted subject — a grounded title for what was left out. A suppressed edge carries no sdd:subject; it is identified by its own skolem instead, the same way an ordinary edge is. sdd:suppresses then names the triple terms excluded, and the set is exactly what the stanza states plus whatever its group's intent implies: for a bodiless %node under an intent group, exactly the intent-membership quad; a %node with a body adds one sdd:suppresses quad per stated line. The set may be empty — a bodiless %node in a group that declares no intent (or a Selection one) states nothing and implies nothing, so it carries no sdd:suppresses at all. That instance is still a complete record: sdd:subject names which depicted thing was left out, which is the whole of what the author said. Only a suppression that could name nothing at all is incoherent — that is why a %edge with no predicate is a build error rather than an empty-set edge suppression: an edge has no sdd:subject to stand in for its excluded relation, so with no predicate it would identify nothing.
The defining property is that claims retain what they suppress: the suppressed quads stay claimed against their source, unlike anything a + line asserts. This is what makes a sdd:Suppression verifiable rather than merely a rendering omission — "exists, we know it, we chose not to depict it" is checkable against the source precisely because the excluded quads are still there.