diff --git a/prisma/schema.prisma b/prisma/schema.prisma
index 89c80d5..98dbed1 100644
--- a/prisma/schema.prisma
+++ b/prisma/schema.prisma
@@ -13,6 +13,7 @@ model Owner {
   pets                Pet[]
   adminRole           AdminRole?
   ban                 UserBan?
+  shadowban           Shadowban?
   issuedInvites       InviteCode[] @relation("IssuedBy")
   legalAcknowledgedAt DateTime?    // last time the owner dismissed the legal-update banner; null = never seen one
   contentRightsConsentedAt  DateTime? // first-pet onboarding: confirms the owner holds all rights to uploaded photos/videos
@@ -623,6 +624,21 @@ model UserBan {
   expiresAt DateTime? // null = permanent ban
 }
 
+// Stealth moderation (Gitea #10 Phase 3) — unlike UserBan, the owner is never
+// told and can still use the app normally. Every reader-facing post query
+// excludes posts from a shadowbanned owner's pets for everyone except that
+// owner's own view (see feed/explore/posts/search/milestones routers), so
+// the content quietly stops reaching anyone else without a visible signal.
+model Shadowban {
+  id             String    @id @default(cuid())
+  owner          Owner     @relation(fields: [ownerId], references: [id], onDelete: Cascade)
+  ownerId        String    @unique
+  reason         String    @db.VarChar(500)
+  shadowbannedAt DateTime  @default(now())
+  shadowbannedBy String    // ownerId of moderator who issued it
+  expiresAt      DateTime? // null = permanent
+}
+
 model Advertisement {
   id        String    @id @default(cuid())
   title     String    @db.VarChar(100)
@@ -693,7 +709,7 @@ model AdRepost {
 
 model ModerationLog {
   id          String   @id @default(cuid())
-  action      String   @db.VarChar(50)  // DELETE_POST | DELETE_COMMENT | BAN_USER | UNBAN_USER | DELETE_IMAGE | DISMISS_REPORT | CREATE_AD | UPDATE_AD | DELETE_AD | GRANT_ROLE | REVOKE_ROLE | WARN_USER | VERIFY_PET | UNVERIFY_PET | DELETE_ACCOUNT | APPROVE_VERIFICATION_REQUEST | REJECT_VERIFICATION_REQUEST | HIDE_POST | UNHIDE_POST
+  action      String   @db.VarChar(50)  // DELETE_POST | DELETE_COMMENT | BAN_USER | UNBAN_USER | DELETE_IMAGE | DISMISS_REPORT | CREATE_AD | UPDATE_AD | DELETE_AD | GRANT_ROLE | REVOKE_ROLE | WARN_USER | VERIFY_PET | UNVERIFY_PET | DELETE_ACCOUNT | APPROVE_VERIFICATION_REQUEST | REJECT_VERIFICATION_REQUEST | HIDE_POST | UNHIDE_POST | SHADOWBAN_USER | UNSHADOWBAN_USER
   targetType  String   @db.VarChar(20)  // POST | COMMENT | USER | IMAGE | AD | REPORT | PET
   targetId    String
   reason      String?  @db.VarChar(500)
diff --git a/src/app/p/[secret]/users/page.tsx b/src/app/p/[secret]/users/page.tsx
index dd22692..29887ff 100644
--- a/src/app/p/[secret]/users/page.tsx
+++ b/src/app/p/[secret]/users/page.tsx
@@ -16,6 +16,7 @@ import {
   BadgeCheck,
   TriangleAlert,
   Trash2,
+  Ghost,
 } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
@@ -36,6 +37,9 @@ export default function AdminUsersPage() {
   const [unbanTarget, setUnbanTarget] = useState<string | null>(null);
   const [banReason, setBanReason] = useState("");
   const [banExpiry, setBanExpiry] = useState("");
+  const [shadowbanTarget, setShadowbanTarget] = useState<string | null>(null);
+  const [unshadowbanTarget, setUnshadowbanTarget] = useState<string | null>(null);
+  const [shadowbanReason, setShadowbanReason] = useState("");
   const [search, setSearch] = useState("");
   const [banStatus, setBanStatus] = useState<BanStatusFilter>("all");
   const [role, setRole] = useState<RoleFilter>("all");
@@ -76,6 +80,25 @@ export default function AdminUsersPage() {
     })
   );
 
+  const shadowbanMutation = useMutation(
+    trpc.admin.shadowbanOwner.mutationOptions({
+      onSuccess: () => {
+        void qc.invalidateQueries({ queryKey: trpc.admin.listUsers.queryKey() });
+        setShadowbanTarget(null);
+        setShadowbanReason("");
+      },
+    })
+  );
+
+  const removeShadowbanMutation = useMutation(
+    trpc.admin.removeShadowban.mutationOptions({
+      onSuccess: () => {
+        void qc.invalidateQueries({ queryKey: trpc.admin.listUsers.queryKey() });
+        setUnshadowbanTarget(null);
+      },
+    })
+  );
+
   const startConversationMutation = useMutation(
     trpc.admin.startTeamConversation.mutationOptions({
       onSuccess: ({ conversationId, teamPetId }) => {
@@ -204,6 +227,14 @@ export default function AdminUsersPage() {
                       BANNED
                     </Badge>
                   )}
+                  {user.shadowban && (
+                    <Badge
+                      variant="secondary"
+                      className="text-[10px] shrink-0 bg-violet-950/60 text-violet-300"
+                    >
+                      SHADOWBANNED
+                    </Badge>
+                  )}
                 </div>
                 {user.clerk && (
                   <p className="text-xs text-zinc-400 mt-0.5 truncate">
@@ -244,6 +275,9 @@ export default function AdminUsersPage() {
                 {user.ban?.reason && (
                   <p className="text-xs text-red-400 mt-0.5">Reason: {user.ban.reason}</p>
                 )}
+                {user.shadowban?.reason && (
+                  <p className="text-xs text-violet-400 mt-0.5">Shadowban: {user.shadowban.reason}</p>
+                )}
               </div>
               <div className="shrink-0 flex items-center gap-2">
                 {user.pets[0] && (
@@ -297,6 +331,29 @@ export default function AdminUsersPage() {
                     <Trash2 className="h-4 w-4" />
                   </Button>
                 )}
+                {user.shadowban ? (
+                  <Button
+                    size="sm"
+                    variant="outline"
+                    className="border-violet-800 text-violet-300 hover:text-violet-100"
+                    onClick={() => setUnshadowbanTarget(user.id)}
+                    title="Remove shadowban"
+                  >
+                    <Ghost className="h-4 w-4 mr-1.5" />
+                    Un-shadowban
+                  </Button>
+                ) : (
+                  <Button
+                    size="sm"
+                    variant="ghost"
+                    className="text-violet-400 hover:text-violet-300"
+                    onClick={() => setShadowbanTarget(user.id)}
+                    title="Shadowban — content quietly stops reaching others, user isn't told"
+                  >
+                    <Ghost className="h-4 w-4 mr-1.5" />
+                    Shadowban
+                  </Button>
+                )}
                 {user.ban ? (
                   <Button
                     size="sm"
@@ -415,6 +472,72 @@ export default function AdminUsersPage() {
         </DialogContent>
       </Dialog>
 
+      {/* Shadowban dialog */}
+      <Dialog
+        open={!!shadowbanTarget}
+        onOpenChange={(o) => { if (!o) { setShadowbanTarget(null); setShadowbanReason(""); } }}
+      >
+        <DialogContent className="bg-zinc-900 border-zinc-800 text-zinc-100 max-w-sm">
+          <DialogHeader>
+            <DialogTitle>Shadowban user</DialogTitle>
+          </DialogHeader>
+          <p className="text-xs text-zinc-500 font-mono break-all">{shadowbanTarget}</p>
+          <p className="text-sm text-zinc-400">
+            Their posts quietly stop reaching anyone else — feed, explore, search, hashtags,
+            profile view. They keep posting normally and are never told.
+          </p>
+          <Input
+            placeholder="Reason (required)"
+            value={shadowbanReason}
+            onChange={(e) => setShadowbanReason(e.target.value)}
+            className="bg-zinc-800 border-zinc-700 text-zinc-100 placeholder:text-zinc-500"
+          />
+          <DialogFooter className="gap-2">
+            <Button variant="ghost" className="text-zinc-400" onClick={() => setShadowbanTarget(null)}>
+              Cancel
+            </Button>
+            <Button
+              className="bg-violet-700 hover:bg-violet-600"
+              onClick={() =>
+                shadowbanMutation.mutate({
+                  ownerId: shadowbanTarget!,
+                  reason: shadowbanReason.trim(),
+                })
+              }
+              disabled={shadowbanMutation.isPending || !shadowbanReason.trim()}
+            >
+              {shadowbanMutation.isPending && <Loader2 className="h-4 w-4 animate-spin mr-2" />}
+              Confirm shadowban
+            </Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+
+      {/* Un-shadowban confirm */}
+      <Dialog open={!!unshadowbanTarget} onOpenChange={(o) => { if (!o) setUnshadowbanTarget(null); }}>
+        <DialogContent className="bg-zinc-900 border-zinc-800 text-zinc-100 max-w-sm">
+          <DialogHeader>
+            <DialogTitle>Remove shadowban</DialogTitle>
+          </DialogHeader>
+          <p className="text-sm text-zinc-400">
+            Restore normal visibility for this user&apos;s posts?
+          </p>
+          <DialogFooter className="gap-2">
+            <Button variant="ghost" className="text-zinc-400" onClick={() => setUnshadowbanTarget(null)}>
+              Cancel
+            </Button>
+            <Button
+              onClick={() => removeShadowbanMutation.mutate({ ownerId: unshadowbanTarget! })}
+              disabled={removeShadowbanMutation.isPending}
+              className="bg-zinc-700 hover:bg-zinc-600"
+            >
+              {removeShadowbanMutation.isPending && <Loader2 className="h-4 w-4 animate-spin mr-2" />}
+              Remove shadowban
+            </Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+
       {/* Warnings history + issue new */}
       <Dialog
         open={!!warnTarget}
diff --git a/src/trpc/routers/admin.ts b/src/trpc/routers/admin.ts
index ac52dee..ed86aaf 100644
--- a/src/trpc/routers/admin.ts
+++ b/src/trpc/routers/admin.ts
@@ -425,6 +425,7 @@ export const adminRouter = router({
         include: {
           pets: { select: { id: true, name: true, avatarKey: true, isVerified: true }, take: 3 },
           ban: true,
+          shadowban: true,
           adminRole: true,
           _count: { select: { pets: true, warnings: true } },
         },
@@ -526,6 +527,54 @@ export const adminRouter = router({
       return { success: true };
     }),
 
+  shadowbanOwner: protectedProcedure
+    .input(z.object({ ownerId: z.string().min(1), reason: z.string().min(1).max(500) }))
+    .mutation(async ({ ctx, input }) => {
+      const callerRole = await assertAdmin(ctx.prisma, ctx.userId, AdminRoleType.MODERATOR);
+      if (input.ownerId === ctx.userId)
+        throw new TRPCError({ code: "BAD_REQUEST", message: "Cannot shadowban yourself." });
+      await ctx.prisma.$transaction([
+        ctx.prisma.shadowban.upsert({
+          where: { ownerId: input.ownerId },
+          create: { ownerId: input.ownerId, reason: input.reason, shadowbannedBy: ctx.userId },
+          update: { reason: input.reason, shadowbannedBy: ctx.userId, shadowbannedAt: new Date() },
+        }),
+        ctx.prisma.moderationLog.create({
+          data: {
+            action: "SHADOWBAN_USER",
+            targetType: "USER",
+            targetId: input.ownerId,
+            reason: input.reason,
+            moderatorId: ctx.userId,
+            moderatorRole: callerRole,
+            ipAddress: ctx.ip,
+          },
+        }),
+      ]);
+      return { success: true };
+    }),
+
+  removeShadowban: protectedProcedure
+    .input(z.object({ ownerId: z.string().min(1) }))
+    .mutation(async ({ ctx, input }) => {
+      const callerRole = await assertAdmin(ctx.prisma, ctx.userId, AdminRoleType.MODERATOR);
+      await ctx.prisma.$transaction([
+        ctx.prisma.shadowban.delete({ where: { ownerId: input.ownerId } }),
+        ctx.prisma.moderationLog.create({
+          data: {
+            action: "UNSHADOWBAN_USER",
+            targetType: "USER",
+            targetId: input.ownerId,
+            reason: null,
+            moderatorId: ctx.userId,
+            moderatorRole: callerRole,
+            ipAddress: ctx.ip,
+          },
+        }),
+      ]);
+      return { success: true };
+    }),
+
   // ─── Warnings (append-only, no delete/edit — Gitea #10 permission matrix) ────
   listWarnings: protectedProcedure
     .input(z.object({ ownerId: z.string().min(1) }))
diff --git a/src/trpc/routers/explore.ts b/src/trpc/routers/explore.ts
index 9c948b5..01d1407 100644
--- a/src/trpc/routers/explore.ts
+++ b/src/trpc/routers/explore.ts
@@ -60,7 +60,12 @@ export const exploreRouter = router({
 
     const [posts, hashtags] = await Promise.all([
       ctx.prisma.post.findMany({
-        where: { createdAt: { gte: since48h }, type: "PHOTO", hiddenAt: null },
+        where: {
+          createdAt: { gte: since48h },
+          type: "PHOTO",
+          hiddenAt: null,
+          pet: { owner: { shadowban: null } },
+        },
         include: {
           images: { orderBy: { position: "asc" } },
           pet: { select: { id: true, name: true, avatarKey: true } },
diff --git a/src/trpc/routers/feed.ts b/src/trpc/routers/feed.ts
index 515e4d9..b7cb262 100644
--- a/src/trpc/routers/feed.ts
+++ b/src/trpc/routers/feed.ts
@@ -67,6 +67,7 @@ async function getDiscoveryPosts(
       pet: {
         speciesId: viewerPet.speciesId,
         id: { notIn: [viewerPet.id, ...blockedPetIds] },
+        owner: { shadowban: null },
       },
     },
     orderBy: { createdAt: "desc" },
@@ -125,6 +126,7 @@ export const feedRouter = router({
           where: {
             hiddenAt: null,
             petId: { in: petIds, notIn: blockedPetIds },
+            pet: { OR: [{ ownerId: ctx.userId }, { owner: { shadowban: null } }] },
             ...(cursorDate ? { createdAt: { lt: cursorDate } } : {}),
           },
           orderBy: { createdAt: "desc" },
@@ -168,7 +170,10 @@ export const feedRouter = router({
         where: {
           id: { in: postIds },
           hiddenAt: null,
-          pet: { id: { notIn: blockedPetIds } },
+          pet: {
+            id: { notIn: blockedPetIds },
+            OR: [{ ownerId: ctx.userId }, { owner: { shadowban: null } }],
+          },
         },
         include: postInclude,
       });
diff --git a/src/trpc/routers/milestones.ts b/src/trpc/routers/milestones.ts
index 831e90d..e6f7ca3 100644
--- a/src/trpc/routers/milestones.ts
+++ b/src/trpc/routers/milestones.ts
@@ -86,7 +86,12 @@ export const milestonesRouter = router({
     )
     .query(async ({ ctx, input }) => {
       return ctx.prisma.post.findMany({
-        where: { petId: input.petId, type: "MILESTONE", hiddenAt: null },
+        where: {
+          petId: input.petId,
+          type: "MILESTONE",
+          hiddenAt: null,
+          pet: { OR: [{ ownerId: ctx.userId }, { owner: { shadowban: null } }] },
+        },
         include: {
           milestone: true,
           images: { orderBy: { position: "asc" } },
diff --git a/src/trpc/routers/posts.ts b/src/trpc/routers/posts.ts
index 1b0b9dd..d98732b 100644
--- a/src/trpc/routers/posts.ts
+++ b/src/trpc/routers/posts.ts
@@ -208,6 +208,7 @@ export const postsRouter = router({
         where: {
           petId: input.petId,
           hiddenAt: null,
+          pet: { OR: [{ ownerId: ctx.userId }, { owner: { shadowban: null } }] },
           ...(input.cursor
             ? { createdAt: { lt: new Date(input.cursor) } }
             : {}),
diff --git a/src/trpc/routers/search.ts b/src/trpc/routers/search.ts
index e9ef95e..afbef79 100644
--- a/src/trpc/routers/search.ts
+++ b/src/trpc/routers/search.ts
@@ -66,7 +66,10 @@ export const searchRouter = router({
       const rows = await ctx.prisma.postHashtag.findMany({
         where: {
           hashtagId: hashtag.id,
-          post: { hiddenAt: null },
+          post: {
+            hiddenAt: null,
+            pet: { OR: [{ ownerId: ctx.userId }, { owner: { shadowban: null } }] },
+          },
           ...(input.cursor ? { postId: { lt: input.cursor } } : {}),
         },
         take: input.limit + 1,