diff --git a/docs/DEVIATIONS.md b/docs/DEVIATIONS.md
index 40dd7e0..9cd009d 100644
--- a/docs/DEVIATIONS.md
+++ b/docs/DEVIATIONS.md
@@ -1376,3 +1376,12 @@ issue #3 未关闭，`feat/fix-3-downlink-deadlock` 未合入 `main`。下面是
    - 原因：注册安全码错误与错误 API 令牌按 IP 建条目，轮换地址会使 map 只增不减。  
    - 备选方案：一并改 `internal/admin/memlock.go`（否决，本波只改 locks.go；admin 测试用内存锁若仍独立注入需后续对齐）。未改对话密码锁键（U-03）。  
    - 影响：过期未锁定条目会被回收；极端并发失败时最早的非锁定计数可能被挤出。
+
+### 复审修复 U-05
+
+1. **目录 LIKE 转义；注册拒绝编号 inline**  
+   - 原条款：DEVELOPMENT 6.5 按编号前缀或名称包含匹配；issue #43。  
+   - 实际做法：目录查询对 `\`、`%`、`_` 转义并 `ESCAPE '\'`。注册拒绝编号 `inline`（与 mochi 内联客户端 ClientID 同名）。  
+   - 原因：未转义时搜 `e_ab` 会命中 `exab…`，搜 `%` 返回全部端。  
+   - 备选方案：在 `internal/protocol.ValidEndpointID` 加保留字，使开通/导入一并拒绝（否决，本波不改 protocol 与 `internal/admin/endpoints.go`）。后台开通与批量导入仍可能使用 `inline`，留给后续波次。  
+   - 影响：目录下划线按字面匹配；自助注册不能占用 `inline`。
diff --git a/internal/app/identity/register.go b/internal/app/identity/register.go
index 5e0743c..c64cbc7 100644
--- a/internal/app/identity/register.go
+++ b/internal/app/identity/register.go
@@ -171,6 +171,9 @@ func (h *RegisterHandler) register(ctx context.Context, req *protocol.RegisterRe
 		}
 		return RegisterResult{}, apiErr(http.StatusBadRequest, code, msg)
 	}
+	if strings.EqualFold(req.ID, "inline") {
+		return RegisterResult{}, apiErr(http.StatusBadRequest, protocol.CodeBadRequest, "id reserved")
+	}
 
 	id := req.ID
 	loginPassword := req.LoginPassword
diff --git a/internal/app/identity/register_test.go b/internal/app/identity/register_test.go
index 2ad8efe..db51c04 100644
--- a/internal/app/identity/register_test.go
+++ b/internal/app/identity/register_test.go
@@ -539,6 +539,18 @@ func TestRegister_LogOmitsSecrets(t *testing.T) {
 	}
 }
 
+func TestRegister_ReservedInlineID(t *testing.T) {
+	env := openTestEnv(t)
+	env.setRegistration(t, true, "inline-code1")
+	code, resp, _ := env.doRegister(t, `{"registration_code":"inline-code1","id":"inline","login_password":"password1"}`)
+	if code != http.StatusBadRequest || resp.Error == nil || resp.Error.Code != protocol.CodeBadRequest {
+		t.Fatalf("status=%d resp=%+v", code, resp)
+	}
+	if _, _, ok := env.getEndpoint(t, "inline"); ok {
+		t.Fatal("inline must not be created")
+	}
+}
+
 func TestRegister_NSTPasswordRejected(t *testing.T) {
 	env := openTestEnv(t)
 	env.setRegistration(t, true, "nst-code-01")
diff --git a/internal/app/presence/app.go b/internal/app/presence/app.go
index f75966f..e5c1ddd 100644
--- a/internal/app/presence/app.go
+++ b/internal/app/presence/app.go
@@ -122,13 +122,15 @@ WHERE id > ?
 ORDER BY id ASC
 LIMIT ?`, cursor, limit+1)
 	} else {
-		like := "%" + strings.ToLower(query) + "%"
-		prefix := strings.ToLower(query) + "%"
+		q := strings.ToLower(query)
+		esc := escapeLikePattern(q)
+		like := "%" + esc + "%"
+		prefix := esc + "%"
 		rows, err = a.db.Read.QueryContext(ctx, `
 SELECT id, name, online_since, offline_since, talk_hash
 FROM endpoints
 WHERE id > ?
-  AND (lower(id) LIKE ? OR lower(name) LIKE ?)
+  AND (lower(id) LIKE ? ESCAPE '\' OR lower(name) LIKE ? ESCAPE '\')
 ORDER BY id ASC
 LIMIT ?`, cursor, prefix, like, limit+1)
 	}
diff --git a/internal/app/presence/like.go b/internal/app/presence/like.go
new file mode 100644
index 0000000..72bec63
--- /dev/null
+++ b/internal/app/presence/like.go
@@ -0,0 +1,16 @@
+package presence
+
+import "strings"
+
+func escapeLikePattern(s string) string {
+	var b strings.Builder
+	b.Grow(len(s) + 4)
+	for _, r := range s {
+		switch r {
+		case '\\', '%', '_':
+			b.WriteByte('\\')
+		}
+		b.WriteRune(r)
+	}
+	return b.String()
+}
diff --git a/internal/app/presence/presence_test.go b/internal/app/presence/presence_test.go
index a46e5e0..8cafcfc 100644
--- a/internal/app/presence/presence_test.go
+++ b/internal/app/presence/presence_test.go
@@ -131,6 +131,35 @@ func TestF03PresenceAndDirectory(t *testing.T) {
 	}
 }
 
+func TestDirectoryLikeEscapesUnderscore(t *testing.T) {
+	t.Parallel()
+	app, db, _ := openPresence(t)
+	ctx := context.Background()
+	insertEP(t, db, "e_ab1", "underscore")
+	insertEP(t, db, "exab2", "wildcard")
+	insertEP(t, db, "pct", "has%percent")
+
+	q, _, err := app.Directory(ctx, &protocol.DirectoryList{
+		V: protocol.Version, Type: protocol.TypeDirectoryList, RID: "u1", Query: "e_ab", Limit: 10,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(q) != 1 || q[0].ID != "e_ab1" {
+		t.Fatalf("want only e_ab1, got %+v", q)
+	}
+
+	q, _, err = app.Directory(ctx, &protocol.DirectoryList{
+		V: protocol.Version, Type: protocol.TypeDirectoryList, RID: "u2", Query: "%", Limit: 10,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(q) != 1 || q[0].ID != "pct" {
+		t.Fatalf("literal %% should not match all, got %+v", q)
+	}
+}
+
 func TestF04PresenceWatch(t *testing.T) {
 	t.Parallel()
 	app, db, down := openPresence(t)