diff --git a/apps/Backend/src/routes/claims.ts b/apps/Backend/src/routes/claims.ts
index 4c56d55f..24706c9f 100755
--- a/apps/Backend/src/routes/claims.ts
+++ b/apps/Backend/src/routes/claims.ts
@@ -740,13 +740,16 @@ router.post(
             if (saved) resolvedNpiProvider = saved;
           }
 
-          // Collect attachments: appointment-level files + claim-level files
+          // Collect attachments: appointment-level files + claim-level files (deduped by filename+path)
           const apptFiles = await storage.getAppointmentFiles(Number(apt.id));
           const claimFiles = (activeClaim as any)?.claimFiles ?? [];
-          const allFileMeta = [
-            ...apptFiles,
-            ...claimFiles,
-          ] as Array<{ filename: string; mimeType?: string | null; filePath?: string | null }>;
+          const seenFileKeys = new Set<string>();
+          const allFileMeta = [...apptFiles, ...claimFiles].filter((f: any) => {
+            const key = `${f.filename ?? ""}::${f.filePath ?? ""}`;
+            if (seenFileKeys.has(key)) return false;
+            seenFileKeys.add(key);
+            return true;
+          }) as Array<{ filename: string; mimeType?: string | null; filePath?: string | null }>;
 
           const filesForQueue = allFileMeta.flatMap((f) => {
             if (!f.filePath) return [];
@@ -1276,17 +1279,33 @@ router.put("/:id", async (req: Request, res: Response): Promise<any> => {
       await syncAppointmentType(existingClaim.appointmentId, updatedCodes);
     }
 
-    // If new claimFiles are provided, append them (don't delete existing ones)
+    // If new claimFiles are provided, append only ones not already attached to this claim
     if (Array.isArray(req.body.claimFiles) && req.body.claimFiles.length > 0) {
       const { prisma: db } = await import("@repo/db/client");
-      await db.claimFile.createMany({
-        data: req.body.claimFiles.map((f: any) => ({
-          claimId,
-          filename: String(f.filename || ""),
-          mimeType: String(f.mimeType || f.mime || ""),
-          ...(f.filePath ? { filePath: String(f.filePath) } : {}),
-        })),
+      const existingFiles = await db.claimFile.findMany({
+        where: { claimId },
+        select: { filename: true, filePath: true },
       });
+      const existingKeys = new Set(
+        existingFiles.map((f: any) => `${f.filename}::${f.filePath ?? ""}`)
+      );
+      const seenKeys = new Set<string>();
+      const newFiles = req.body.claimFiles.filter((f: any) => {
+        const key = `${String(f.filename || "")}::${String(f.filePath || "")}`;
+        if (existingKeys.has(key) || seenKeys.has(key)) return false;
+        seenKeys.add(key);
+        return true;
+      });
+      if (newFiles.length > 0) {
+        await db.claimFile.createMany({
+          data: newFiles.map((f: any) => ({
+            claimId,
+            filename: String(f.filename || ""),
+            mimeType: String(f.mimeType || f.mime || ""),
+            ...(f.filePath ? { filePath: String(f.filePath) } : {}),
+          })),
+        });
+      }
     }
 
     // Explicitly pick only scalar fields — skip serviceLines and claimFiles (handled above)