diff --git a/docs/data-model.md b/docs/data-model.md
index 3c0f9bdd..441d1830 100644
--- a/docs/data-model.md
+++ b/docs/data-model.md
@@ -1267,7 +1267,11 @@ own pod, as a draft, before publishing it
   made, its sources) is written as it is, and kept through every edit;
   the Studio's release screen writes it as the library's releases do
   ([deck-library.md](deck-library.md#provenance),
-  [studio.md](studio.md#the-releases-metadata-and-provenance)). A
+  [studio.md](studio.md#the-releases-metadata-and-provenance)). Of the
+  classes another app gives a subject the draft reads by its shape, the
+  draft keeps only those the subject's write would keep
+  ([shapes.md](shapes.md#conventions)), so none of them stops an edit.
+  The release published from it leaves the others out too. A
   draft names the release it was published as with `sm:releasedAs`, and
   is then no longer edited. An `sm:releasedAs` at an address no release
   can have (`isPublishedReleaseUrl`, as for the catalog's releases) is
diff --git a/docs/shapes.md b/docs/shapes.md
index 07b59fbc..235ff265 100644
--- a/docs/shapes.md
+++ b/docs/shapes.md
@@ -120,7 +120,12 @@ check a draft's cards, distractors, agents and distributions.
   blank node, names no class but counts toward that number, so the
   writer leaves it out of the subject it checks and writes. A
   blank node stays in a document Solid Memo patches rather than
-  rewrites, but no write counts it again.
+  rewrites, but no write counts it again. A release draft keeps another
+  app's statements of its subjects as they are. So it reads and writes
+  the classes of its deck, chapters, steps, cards, distractors, agents
+  and distributions by the same rule (`keptClasses` in
+  [records.ts](../packages/solid/src/records.ts)). Publishing leaves
+  out of the release each class the draft doesn't keep.
 - **Property shapes are named** (`<#front>`, never blank nodes) for the
   generator and the results. `sh:message` replaces cryptic engine
   text, always in exactly English and Swedish (`"…"@en`, `"…"@sv`),
diff --git a/packages/solid/src/mappers/releaseDraftMapper.ts b/packages/solid/src/mappers/releaseDraftMapper.ts
index 0b42ee3a..15b65978 100644
--- a/packages/solid/src/mappers/releaseDraftMapper.ts
+++ b/packages/solid/src/mappers/releaseDraftMapper.ts
@@ -41,7 +41,14 @@ import { migrate } from "@solid-memo/domain/shapes/migrations";
 import { DRAFT_DECK_V1, SHAPES } from "@solid-memo/vocab/descriptors.generated";
 import type { ShapeDescriptor } from "@solid-memo/vocab/shapeDescriptor";
 import type { ShapeName } from "@solid-memo/vocab/types.generated";
-import { datetimeOf, readIris, readRecord, readVersioned, recordThing } from "../records";
+import {
+  datetimeOf,
+  keptClasses,
+  readIris,
+  readRecord,
+  readVersioned,
+  recordThing,
+} from "../records";
 import { DCTERMS, SM } from "../vocab";
 
 /**
@@ -381,8 +388,24 @@ function hiddenPredicateOf(
 export function draftFromQuads(
   quads: readonly Quad[],
   url: string,
-  { refuseHidden = false }: { refuseHidden?: boolean } = {},
+  options: { refuseHidden?: boolean } = {},
 ): ReleaseDraft | null {
+  return draftReadOf(quads, url, options)?.draft ?? null;
+}
+
+/**
+ * The draft `quads` state (draftFromQuads), and which classes it does not
+ * keep: `unkept(subject, object)` holds of an rdf:type of a subject the
+ * draft reads by its shape (`subject` its key, `object` as the draft
+ * names it) that is neither one of its own nor one keptClasses keeps of
+ * the others. Publishing leaves those out of the release, as the draft
+ * it checks does (GHSA-8hh7-p2ww-mpjf).
+ */
+export function draftReadOf(
+  quads: readonly Quad[],
+  url: string,
+  { refuseHidden = false }: { refuseHidden?: boolean } = {},
+): { draft: ReleaseDraft; unkept: (subject: string, object: ReleaseTerm) => boolean } | null {
   const dataset = datasetFromQuads(quads);
   /** Each subject's statements, by its key. */
   const statements = new Map<string, Quad[]>();
@@ -480,11 +503,33 @@ export function draftFromQuads(
     own(subject, descriptor);
     nodes[list]!.push({ id, data });
   }
+  // Of the other classes a shaped subject states, only those its write
+  // keeps (keptClasses): a class a shape asks something of, one past the
+  // most the write check reads, or a type that is no IRI would stop
+  // every write of the subject (GHSA-8hh7-p2ww-mpjf).
+  const classes = new Map<string, string[]>();
+  for (const quad of quads) {
+    const subject = keyOf(quad.subject);
+    if (!owned.has(subject) || !isClass(quad)) continue;
+    const of = classes.get(subject);
+    if (of === undefined) classes.set(subject, [quad.object.value]);
+    else of.push(quad.object.value);
+  }
+  const kept = new Map(
+    [...classes].map(([subject, types]) => [
+      subject,
+      new Set(keptClasses(owned.get(subject)!.types, types)),
+    ]),
+  );
+  const unkept = (subject: string, object: ReleaseTerm) =>
+    owned.has(subject) && (object.kind !== "iri" || !kept.get(subject)!.has(object.value));
   const triples = quads
     .filter((quad) => {
-      const shaped = owned.get(keyOf(quad.subject));
+      const subject = keyOf(quad.subject);
+      const shaped = owned.get(subject);
       if (shaped === undefined) return true;
-      if (quad.predicate.value === RDF_TYPE) return !shaped.types.has(quad.object.value);
+      if (quad.predicate.value === RDF_TYPE)
+        return !shaped.types.has(quad.object.value) && !unkept(subject, termOf(quad.object));
       return !shaped.predicates.has(quad.predicate.value);
     })
     .map(
@@ -494,7 +539,7 @@ export function draftFromQuads(
         object: termOf(quad.object),
       }),
     );
-  return {
+  const draft: ReleaseDraft = {
     url,
     course: rootTypes.includes(SCHEMA_COURSE),
     root,
@@ -505,6 +550,7 @@ export function draftFromQuads(
     triples,
     published: NOTHING_PUBLISHED,
   };
+  return { draft, unkept };
 }
 
 /** One subject of a draft as its document in the pod holds it: its record, when its shape describes it, and its other statements. */
@@ -647,10 +693,36 @@ export function entryQuads(entry: DraftEntry): Quad[] {
             recordThing(entry.subject, entry.shaped.descriptor, entry.shaped.record, null),
           ),
         );
-  return [
+  return withEntryClasses(entry, [
     ...shaped,
     ...entry.raw.map((triple) => quadOf(triple.subject, triple.predicate, triple.object)),
-  ];
+  ]);
+}
+
+/** Whether the quad states a class of its subject: an rdf:type that is an IRI. */
+function isClass(quad: Quad): boolean {
+  return quad.predicate.value === RDF_TYPE && quad.object.termType === "NamedNode";
+}
+
+/**
+ * The quads of an entry with the classes its subject's write would not
+ * keep left out, when its shape describes it: each its own, and of the
+ * others only those keptClasses keeps, so that what a draft writes of a
+ * shaped subject is held to its own shapes alone, whatever its
+ * statements carry (GHSA-8hh7-p2ww-mpjf). A type that is no IRI goes too.
+ */
+export function withEntryClasses(entry: DraftEntry, quads: readonly Quad[]): Quad[] {
+  if (entry.shaped === undefined) return [...quads];
+  const { descriptor } = entry.shaped;
+  const typed = (quad: Quad) =>
+    quad.predicate.value === RDF_TYPE && keyOf(quad.subject) === entry.subject;
+  const kept = new Set(
+    keptClasses(
+      [descriptor.targetClass, ...descriptor.additionalTypes],
+      quads.filter((quad) => typed(quad) && isClass(quad)).map((quad) => quad.object.value),
+    ),
+  );
+  return quads.filter((quad) => !typed(quad) || (isClass(quad) && kept.has(quad.object.value)));
 }
 
 /** Whether two entries say the same of their subject, in the same place. */
diff --git a/packages/solid/src/records.ts b/packages/solid/src/records.ts
index dd9b3931..bc03ba3b 100644
--- a/packages/solid/src/records.ts
+++ b/packages/solid/src/records.ts
@@ -433,19 +433,36 @@ export function withoutForeignShapedClasses(
   thing: NamedSubject,
   descriptor: ShapeDescriptor,
 ): NamedSubject {
-  const own = new Set([descriptor.targetClass, ...descriptor.additionalTypes]);
-  let room = MAX_CLASSES - own.size;
+  const kept = keptClasses(
+    [descriptor.targetClass, ...descriptor.additionalTypes],
+    getUrlAll(thing, RDF.type),
+  );
+  // A value of rdf:type that is no IRI (a literal, a blank node) names
+  // no class, yet the check counts it against MAX_CLASSES: it goes too.
+  return buildThing(thing).removeAll(RDF.type).setIriAll(RDF.type, kept).build();
+}
+
+/**
+ * Of the classes a subject states (`classes`, IRIs in the order it
+ * states them), the ones it keeps when its own are `own`: each of its
+ * own, and each class no shape asks anything of (SHAPED_CLASSES) while
+ * the subject, its own classes first, stays within the most the write
+ * check reads it by (MAX_CLASSES). The rule withoutForeignShapedClasses
+ * writes a subject by, for a writer that keeps a subject's classes as
+ * statements of its own (a release draft's).
+ */
+export function keptClasses(own: Iterable<string>, classes: Iterable<string>): string[] {
+  const owned = new Set(own);
+  let room = MAX_CLASSES - owned.size;
   const kept: string[] = [];
-  for (const type of new Set(getUrlAll(thing, RDF.type))) {
-    if (own.has(type)) kept.push(type);
+  for (const type of new Set(classes)) {
+    if (owned.has(type)) kept.push(type);
     else if (!SHAPED_CLASSES.has(type) && room > 0) {
       kept.push(type);
       room--;
     }
   }
-  // A value of rdf:type that is no IRI (a literal, a blank node) names
-  // no class, yet the check counts it against MAX_CLASSES: it goes too.
-  return buildThing(thing).removeAll(RDF.type).setIriAll(RDF.type, kept).build();
+  return kept;
 }
 
 /**
diff --git a/packages/solid/src/solidReleaseDraftRepository.test.ts b/packages/solid/src/solidReleaseDraftRepository.test.ts
index 27537c29..2d4b4aff 100644
--- a/packages/solid/src/solidReleaseDraftRepository.test.ts
+++ b/packages/solid/src/solidReleaseDraftRepository.test.ts
@@ -14,6 +14,7 @@ import { ruleProblems } from "@solid-memo/domain/release/releaseCheck";
 import {
   applyDraftChanges,
   blankDraft,
+  iriIn,
   isRefusal,
   type DraftChange,
   type DraftNode,
@@ -2040,3 +2041,151 @@ describe("a release with a card outside it (GHSA-67w8-qjpm-jhwp)", () => {
     ]);
   });
 });
+
+describe("a class another app gives a draft's subject (GHSA-8hh7-p2ww-mpjf)", () => {
+  const PALETTE = `${SM}Palette`;
+  const OTHER = "http://example.org/Other";
+  const CARD = `${CHAPTER_A}#q-a-2a`;
+  const typeOf = (subject: string, object: string) => `\n<${subject}> <${RDF}type> ${object} .\n`;
+
+  /** The course fixture with `turtle` added to `document` as another app would, read again. */
+  async function planted(document: string, turtle: string) {
+    const pod = await draftPod({ checked: true });
+    await pod.repository.create(INSTANCE, course());
+    await pod.put(document, `${await pod.text(document)}${turtle}`);
+    const { draft, version } = await pod.repository.read(DRAFT);
+    return { pod, draft, version };
+  }
+
+  /** The classes the draft keeps of `subject` as statements of its own. */
+  const keptTypes = (draft: ReleaseDraft, subject: string) =>
+    draft.triples
+      .filter((triple) => triple.subject === subject && triple.predicate === `${RDF}type`)
+      .map((triple) => triple.object.value);
+
+  it("leaves a shaped class on the root out, so its edit is written", async () => {
+    const { pod, draft, version } = await planted(DRAFT, typeOf(DRAFT, `<${PALETTE}>`));
+    expect(keptTypes(draft, DRAFT)).toEqual([]);
+    await pod.repository.applyChanges(
+      draft,
+      changed(draft, { kind: "setMeta", meta: { title: { en: "New" } } }),
+      version,
+    );
+    expect(await pod.text(DRAFT)).not.toContain(PALETTE);
+    const { draft: read } = await pod.repository.read(DRAFT);
+    expect(read.root.title).toEqual({ en: "New" });
+  });
+
+  it("leaves a shaped class on a card out, so its edit is written", async () => {
+    const { pod, draft, version } = await planted(CHAPTER_A, typeOf(CARD, `<${PALETTE}>`));
+    expect(keptTypes(draft, iriIn(draft, "q-a-2a"))).toEqual([]);
+    await pod.repository.applyChanges(
+      draft,
+      changed(draft, {
+        kind: "editCard",
+        id: "q-a-2a",
+        card: { front: { en: "New?" }, back: { en: "Yes" } },
+      }),
+      version,
+    );
+    expect(await pod.text(CHAPTER_A)).not.toContain(PALETTE);
+  });
+
+  it("keeps a class no shape asks anything of through an edit", async () => {
+    const { pod, draft, version } = await planted(DRAFT, typeOf(DRAFT, `<${OTHER}>`));
+    expect(keptTypes(draft, DRAFT)).toEqual([OTHER]);
+    await pod.repository.applyChanges(
+      draft,
+      changed(draft, { kind: "setMeta", meta: { title: { en: "New" } } }),
+      version,
+    );
+    const { draft: read } = await pod.repository.read(DRAFT);
+    expect(keptTypes(read, DRAFT)).toEqual([OTHER]);
+  });
+
+  it("keeps no more classes than the write check reads, and no type that is no IRI", async () => {
+    const many = Array.from({ length: 40 }, (_, at) => `<${OTHER}${at}>`).join(" , ");
+    const { pod, draft, version } = await planted(
+      DRAFT,
+      `${typeOf(DRAFT, many)}${typeOf(DRAFT, '"Deck"')}${typeOf(DRAFT, "_:b")}`,
+    );
+    const kept = keptTypes(draft, DRAFT);
+    // Its own classes (sm:Deck, dcat:Dataset) and schema:Course count first.
+    expect(kept).toHaveLength(32 - 3);
+    expect(kept.every((type) => type.startsWith(OTHER))).toBe(true);
+    await pod.repository.applyChanges(
+      draft,
+      changed(draft, { kind: "setMeta", meta: { title: { en: "New" } } }),
+      version,
+    );
+    const text = await pod.text(DRAFT);
+    expect(text).not.toContain('"Deck"');
+    const { draft: read } = await pod.repository.read(DRAFT);
+    expect(keptTypes(read, DRAFT)).toEqual(kept);
+  });
+
+  it("writes no shaped class a draft's statements carry, made or changed", async () => {
+    const carried = (draft: ReleaseDraft, subject: string): ReleaseDraft => ({
+      ...draft,
+      triples: [
+        ...draft.triples,
+        { subject, predicate: `${RDF}type`, object: { kind: "iri", value: PALETTE } },
+        { subject, predicate: `${RDF}type`, object: { kind: "blank", value: "b" } },
+      ],
+    });
+    const pod = await draftPod({ checked: true });
+    await pod.repository.create(INSTANCE, carried(course(), DRAFT));
+    expect(await pod.text(DRAFT)).not.toContain(PALETTE);
+    const { draft, version } = await pod.repository.read(DRAFT);
+    const card = iriIn(draft, "q-a-2a");
+    await pod.repository.applyChanges(
+      draft,
+      carried(
+        changed(draft, {
+          kind: "editCard",
+          id: "q-a-2a",
+          card: { front: { en: "New?" }, back: { en: "Yes" } },
+        }),
+        card,
+      ),
+      version,
+    );
+    expect(await pod.text(CHAPTER_A)).not.toContain(PALETTE);
+  });
+});
+
+describe("publishing a draft whose subject another app gave a class (GHSA-8hh7-p2ww-mpjf)", () => {
+  const PALETTE = `${SM}Palette`;
+  const OTHER = "http://example.org/Other";
+  const DISTRACTOR = `${CHAPTER_A}#q-a-1a-d1`;
+  const typeOf = (subject: string, object: string) => `\n<${subject}> <${RDF}type> ${object} .\n`;
+
+  it("leaves a class the draft does not keep out of the release, as of the draft checked", async () => {
+    const pod = await draftPod({ checked: true });
+    await pod.repository.create(INSTANCE, course());
+    await pod.put(
+      CHAPTER_A,
+      `${await pod.text(CHAPTER_A)}${typeOf(DISTRACTOR, `<${PALETTE}>`)}${typeOf(DISTRACTOR, '"Deck"')}`,
+    );
+    await pod.put(
+      DRAFT,
+      `${await pod.text(DRAFT)}${typeOf(DRAFT, `<${PALETTE}>`)}${typeOf(DRAFT, `<${OTHER}>`)}`,
+    );
+    const { version } = await pod.repository.read(DRAFT);
+    const target = `${INSTANCE}releases/solid/v1.ttl`;
+    const quads = await quadsOfTurtle(
+      await pod.repository.assemble(DRAFT, target, NOW, version),
+      target,
+    );
+    const classesOf = (subject: string) =>
+      quads
+        .filter((quad) => quad.subject.value === subject && quad.predicate.value === `${RDF}type`)
+        .map((quad) => quad.object.value);
+    expect(classesOf(target)).not.toContain(PALETTE);
+    expect(classesOf(target)).toContain(OTHER);
+    expect(classesOf(`${target}#q-a-1a-d1`)).toEqual([
+      `${SM}Distractor`,
+      "https://schema.org/Answer",
+    ]);
+  });
+});
diff --git a/packages/solid/src/solidReleaseDraftRepository.ts b/packages/solid/src/solidReleaseDraftRepository.ts
index 042eb807..a0d71ac3 100644
--- a/packages/solid/src/solidReleaseDraftRepository.ts
+++ b/packages/solid/src/solidReleaseDraftRepository.ts
@@ -36,7 +36,7 @@ import {
   type ReleaseDraftSummary,
 } from "@solid-memo/domain/release/draftLayout";
 import { seriesAbove } from "@solid-memo/domain/release/continuityRules";
-import { DCAT_NS, DCTERMS_NS } from "@solid-memo/domain/release/releaseModel";
+import { DCAT_NS, DCTERMS_NS, type ReleaseTerm } from "@solid-memo/domain/release/releaseModel";
 import {
   RDF_TYPE,
   type DraftTriple,
@@ -58,8 +58,10 @@ import {
 import {
   draftEntries,
   draftFromQuads,
+  draftReadOf,
   draftIriOf,
   entryQuads,
+  withEntryClasses,
   inPlaceIn,
   keyOf,
   quadOf,
@@ -398,22 +400,35 @@ export function createSolidReleaseDraftRepository({
           // So would one of the draft's own subjects named otherwise than the draft writes it, which no read of the draft has (GHSA-8w75-jg23-rxq5).
           if (quad.subject.termType !== "BlankNode" && !inPlace(urls[at]!, quad.subject.value))
             throw new AppError("draftAliasedSubject", { subject: quad.subject.value });
-          return quadOf(
-            quad.subject.termType === "BlankNode"
-              ? `_:${label(quad.subject.value)}`
-              : to(quad.subject.value),
-            quad.predicate.value,
-            object.kind === "iri"
-              ? { kind: "iri", value: to(object.value) }
-              : object.kind === "blank"
-                ? { kind: "blank", value: label(object.value) }
-                : object,
-          );
+          // A class the draft does not keep of its subject is left out of the release, as of the draft checked (GHSA-8hh7-p2ww-mpjf).
+          const typed = classStated(quad, object, iriOf);
+          return {
+            typed,
+            quad: quadOf(
+              quad.subject.termType === "BlankNode"
+                ? `_:${label(quad.subject.value)}`
+                : to(quad.subject.value),
+              quad.predicate.value,
+              object.kind === "iri"
+                ? { kind: "iri", value: to(object.value) }
+                : object.kind === "blank"
+                  ? { kind: "blank", value: label(object.value) }
+                  : object,
+            ),
+          };
         }),
       );
       // So would a value of one of its subjects stated otherwise than its record writes it, which no read of the draft shows (GHSA-32jq-jh7h-r7v4).
-      draftFromQuads(draftNamedQuads(draftUrl, urls, datasets), draftUrl, { refuseHidden: true });
-      const quads = releaseQuadsOf(atTarget, targetUrl, issued);
+      const read = draftReadOf(draftNamedQuads(draftUrl, urls, datasets), draftUrl, {
+        refuseHidden: true,
+      });
+      const quads = releaseQuadsOf(
+        atTarget
+          .filter(({ typed }) => typed === null || !read?.unkept(typed.subject, typed.object))
+          .map(({ quad }) => quad),
+        targetUrl,
+        issued,
+      );
       const subjects = [...new Set(quads.map((quad) => keyOf(quad.subject)))];
       return turtleOf(quads, {
         base: targetUrl,
@@ -525,6 +540,23 @@ function versionOfDocuments(urls: readonly string[], datasets: readonly Dataset[
   return JSON.stringify(urls.map((url, at) => [url, readNumberOf(datasets[at]!)]));
 }
 
+/**
+ * What a statement of a draft's document says, when it states a class of
+ * a named subject: that subject and the class, as the draft names them;
+ * null otherwise.
+ */
+function classStated(
+  quad: Quad,
+  object: ReleaseTerm,
+  iriOf: (iri: string) => string,
+): { subject: string; object: ReleaseTerm } | null {
+  if (quad.subject.termType === "BlankNode" || quad.predicate.value !== RDF_TYPE) return null;
+  return {
+    subject: iriOf(quad.subject.value),
+    object: object.kind === "iri" ? { kind: "iri", value: iriOf(object.value) } : object,
+  };
+}
+
 /**
  * The statements of a draft's documents (`urls`, read as `datasets`),
  * every IRI as the draft names it, as a read of the draft takes them: a
@@ -767,7 +799,8 @@ function involvesBlank(entry: DraftEntry): boolean {
  * (`existing`): its record written over what its shape owns (recordThing,
  * which refuses what a newer app wrote), the statements it said before
  * (`was`) and does not now taken out, those it says now put in; anything
- * else the document says of it kept.
+ * else the document says of it kept, but of its classes only those its
+ * write keeps (withEntryClasses).
  */
 function rewritten(
   existing: NamedSubject | null,
@@ -786,10 +819,10 @@ function rewritten(
       : quadsOf(setThing(createSolidDataset(), base)).filter(
           (quad) => !removed.has(tripleKey(tripleParts(asTriple(quad)))),
         );
-  const quads = [
+  const quads = withEntryClasses(entry, [
     ...kept,
     ...entry.raw.map((triple) => quadOf(triple.subject, triple.predicate, triple.object)),
-  ];
+  ]);
   // The entry says something of its subject (a record's type, or a statement): the subject is there.
   return getThing(datasetFromQuads(quads), entry.subject)!;
 }