diff --git a/apps/web/src/api.ts b/apps/web/src/api.ts
index e525969bb..3362dcf92 100644
--- a/apps/web/src/api.ts
+++ b/apps/web/src/api.ts
@@ -39,7 +39,7 @@ export const ArtifactListItemSchema = type({
   source: "Record<string, unknown>",
   version: "number",
   ownerPrincipalId: "string | null",
-  ownerName: "string | null",
+  metadata: "Record<string, unknown> | null",
   archivedAt: "string | null",
   createdAt: "string",
   updatedAt: "string",
diff --git a/apps/web/src/chat-artifact-open.test.ts b/apps/web/src/chat-artifact-open.test.ts
index 31d695f65..c3b912933 100644
--- a/apps/web/src/chat-artifact-open.test.ts
+++ b/apps/web/src/chat-artifact-open.test.ts
@@ -66,7 +66,7 @@ function artifactDetail(overrides: Partial<ArtifactDetail>): ArtifactDetail {
     source: { origin: "workflow", runId: "run_1" },
     version: 1,
     ownerPrincipalId: null,
-    ownerName: null,
+    metadata: null,
     archivedAt: null,
     createdAt: "2026-08-01T00:00:00.000Z",
     updatedAt: "2026-08-01T00:00:00.000Z",
diff --git a/apps/web/src/library/artifact-card.tsx b/apps/web/src/library/artifact-card.tsx
index b5490cf2a..c91e59157 100644
--- a/apps/web/src/library/artifact-card.tsx
+++ b/apps/web/src/library/artifact-card.tsx
@@ -29,9 +29,6 @@ function metaLine(
   now: number | undefined,
 ): string {
   const parts: string[] = [];
-  if (artifact.ownerName !== null && artifact.ownerName !== "") {
-    parts.push(artifact.ownerName);
-  }
   if (meta?.sourceChannel !== undefined && meta.sourceChannel !== null) {
     parts.push(meta.sourceChannel);
   }
diff --git a/apps/web/src/library/artifact-summary.ts b/apps/web/src/library/artifact-summary.ts
index f51dcbcb5..50d37bbfc 100644
--- a/apps/web/src/library/artifact-summary.ts
+++ b/apps/web/src/library/artifact-summary.ts
@@ -11,7 +11,6 @@ export const ArtifactSummary = type({
    * "csv", "one-pager". Never a closed union: the hub cannot enumerate every
    * kind a workflow might one day emit. */
   kind: "string",
-  ownerName: "string | null",
   createdAt: "string",
   "updatedAt?": "string | null",
 });
diff --git a/apps/web/src/library/artifacts.test.ts b/apps/web/src/library/artifacts.test.ts
index 9090bcc02..62d1157d3 100644
--- a/apps/web/src/library/artifacts.test.ts
+++ b/apps/web/src/library/artifacts.test.ts
@@ -10,7 +10,6 @@ function artifact(overrides: Partial<ArtifactSummary> & { readonly id: string })
   return {
     title: "Untitled",
     kind: "document",
-    ownerName: null,
     createdAt: "2026-01-01T00:00:00.000Z",
     ...overrides,
   };
@@ -22,7 +21,6 @@ describe("ArtifactSummary", () => {
       id: "art_1",
       title: "Q3 report",
       kind: "deck",
-      ownerName: "Ada",
       createdAt: "2026-01-01T00:00:00.000Z",
     });
     expect(parsed).not.toBeInstanceOf(Error);
diff --git a/apps/web/src/pages/library-page.tsx b/apps/web/src/pages/library-page.tsx
index 44e436c45..376ae469a 100644
--- a/apps/web/src/pages/library-page.tsx
+++ b/apps/web/src/pages/library-page.tsx
@@ -115,7 +115,6 @@ function ArtifactRows({
           </TableHead>
           <TableHead>Title</TableHead>
           <TableHead>Kind</TableHead>
-          <TableHead>Owner</TableHead>
           <TableHead>Updated</TableHead>
         </TableRow>
       </TableHeader>
@@ -161,7 +160,6 @@ function ArtifactRows({
               <TableCell className="text-muted-foreground">
                 {artifactKindLabel(artifact.kind)}
               </TableCell>
-              <TableCell className="text-muted-foreground">{artifact.ownerName ?? "—"}</TableCell>
               <TableCell className="text-muted-foreground">
                 {formatRelativeTime(artifact.updatedAt ?? artifact.createdAt, now)}
               </TableCell>
@@ -233,7 +231,6 @@ function PreviewPane({
           {detail !== null ? (
             <p className="truncate text-xs text-muted-foreground">
               {artifactKindLabel(detail.kind)}
-              {detail.ownerName !== null ? ` · ${detail.ownerName}` : ""}
               {` · Version ${detail.version}`}
             </p>
           ) : null}
diff --git a/apps/web/src/shell/library-artifacts.test.ts b/apps/web/src/shell/library-artifacts.test.ts
index 1f25ef983..4d8559361 100644
--- a/apps/web/src/shell/library-artifacts.test.ts
+++ b/apps/web/src/shell/library-artifacts.test.ts
@@ -19,7 +19,6 @@ const sample: ArtifactListRow = {
   id: "art_1",
   kind: "file",
   title: "Quarterly report.pdf",
-  ownerName: "Ada",
   createdAt: "2026-01-01T00:00:00.000Z",
   updatedAt: "2026-01-02T00:00:00.000Z",
 };
@@ -30,7 +29,6 @@ describe("library-artifacts", () => {
       id: "art_1",
       title: "Quarterly report.pdf",
       kind: "file",
-      ownerName: "Ada",
       createdAt: "2026-01-01T00:00:00.000Z",
       updatedAt: "2026-01-02T00:00:00.000Z",
     });
@@ -42,13 +40,11 @@ describe("library-artifacts", () => {
       id: "art_2",
       kind: "document",
       title: "notes.txt",
-      ownerName: null,
     };
     const mapped = mapArtifactListToSummaries([sample, second]);
     expect(mapped).toHaveLength(2);
     expect(mapped[0]?.id).toBe("art_1");
     expect(mapped[1]?.kind).toBe("document");
-    expect(mapped[1]?.ownerName).toBeNull();
   });
 
   test("detects the unconfigured-plane status", () => {
diff --git a/apps/web/src/shell/library-artifacts.ts b/apps/web/src/shell/library-artifacts.ts
index 5f5b725ac..9dbbd69ce 100644
--- a/apps/web/src/shell/library-artifacts.ts
+++ b/apps/web/src/shell/library-artifacts.ts
@@ -17,7 +17,6 @@ export type ArtifactListRow = {
   readonly id: string;
   readonly kind: string;
   readonly title: string;
-  readonly ownerName: string | null;
   readonly createdAt: string;
   readonly updatedAt: string;
 };
@@ -34,7 +33,6 @@ export function artifactListRowToSummary(row: ArtifactListRow): ArtifactSummary
     id: row.id,
     title: row.title,
     kind: row.kind,
-    ownerName: row.ownerName,
     createdAt: row.createdAt,
     updatedAt: row.updatedAt,
   };