diff --git a/README.md b/README.md
index fdaaa5d..b7c6134 100644
--- a/README.md
+++ b/README.md
@@ -263,6 +263,7 @@ Company-scoped POS terminals. Auth via `resolveCompanyAccess`.
 
 | Method | Signature | Returns |
 | --- | --- | --- |
+| `listSearchIndex` | `(googleAuthId, companyId)` | `[{ id, sku, name, eans }]` |
 | `createUnderParent` | `({ googleAuthId, parentId, name })` | `{ id, parentId, name, sku }` |
 | `getBySku` | `(googleAuthId, sku)` | detail object (see below) |
 | `updateBySku` | `(googleAuthId, sku, { name?, unitamount?, unitSi? })` | same shape as `getBySku` |
@@ -310,6 +311,8 @@ Company-scoped POS terminals. Auth via `resolveCompanyAccess`.
 
 `getCategoryArticles` / `getTreeForCompany().articles[]` keep the flat list shape (`net`, `taxRate`, single `fullHash`/`thumbW`/`thumbH`/`thumbHash`).
 
+`listSearchIndex` returns every article in the company (reachable via the category tree) with `id`, `sku`, `name`, and `eans` (all EANs as a flat string array). Designed for client-side search / autocomplete preload. Auth via `resolveCompanyAccess`. Errors: `Company not found`, `Not authorized`.
+
 `parentId` is the category id. Creates `article` + `articletext` (company default language) + `categoryarticle` in one transaction. Allocates `sku` via `getnextnumberwithprefixandpadding` (`type` `sku`; creates `numbers` row with empty prefix if missing). Default unit `pc` is ensured if missing (`unitamount` 1, `weight` 0). Auth via `resolveCategoryAccess(googleAuthId, parentId)` — `Parent not found` / `Not authorized`.
 
 Auth via the article's `categoryarticle` category + `resolveCategoryAccess`. Errors: `Article not found`, `Not authorized`.
@@ -324,7 +327,7 @@ Auth via the article's `categoryarticle` category + `resolveCategoryAccess`. Err
 
 `setWeightBySku` sets the article’s `weight`. Must be finite and `>= 0` (else `Invalid weight`). Errors: `Article not found`, `Not authorized`, `Invalid weight`.
 
-`setCategoryIdsBySku` replaces the article’s category list (`categoryarticle`) in one transaction. Each category must belong to the article’s company and ids must be unique (else `Invalid categoryIds`); empty array removes the article from all categories. Returns the same object as `getBySku` (whose `categoryIds` reflects the new list). Errors: `Article not found`, `Not authorized`, `Invalid categoryIds`.
+`setCategoryIdsBySku` replaces the article’s category list (`categoryarticle`) in one transaction. Each category must belong to the article’s company and ids must be unique (else `Invalid categoryIds`); empty array is rejected — an article must have at least one category (else `Article must have at least one category`). Returns the same object as `getBySku` (whose `categoryIds` reflects the new list). Errors: `Article not found`, `Not authorized`, `Invalid categoryIds`, `Article must have at least one category`.
 
 `deleteImage` removes `articlepic` and the `pic` row for this article (`fullHash`). Errors: `Article not found`, `Image not found`, `Not authorized`.
 
@@ -394,6 +397,7 @@ res.set('Content-Type', thumb.contentType).send(thumb.buffer);
 | `DELETE /api/posterminal/:id/categories` | `posterminal.setOffAll(googleAuthId, companyId, id)` |
 | `POST /api/article` | `article.createUnderParent({ googleAuthId, parentId, name })` |
 | `GET /api/article/:sku` | `article.getBySku(googleAuthId, sku)` |
+| `GET /api/articles/search-index` | `article.listSearchIndex(googleAuthId, companyId)` |
 | `PATCH /api/article/:sku` | `article.updateBySku(googleAuthId, sku, { name?, unitamount?, unitSi? })` |
 | `PUT /api/article/:sku/prices` | `article.setPricesBySku(googleAuthId, sku, [{ price, tax, minmultiplier? }])` |
 | `PUT /api/article/:sku/eans` | `article.setEansBySku(googleAuthId, sku, string[])` |
diff --git a/src/index.js b/src/index.js
index c1ff815..63f6f1c 100644
--- a/src/index.js
+++ b/src/index.js
@@ -20,6 +20,7 @@ import articleOrderImages from './store/article/orderImages.js';
 import articleAddImage from './store/article/addImage.js';
 import articleCreateUnderParent from './store/article/createUnderParent.js';
 import articleGetBySku from './store/article/getBySku.js';
+import articleListSearchIndex from './store/article/listSearchIndex.js';
 import articleUpdateBySku from './store/article/updateBySku.js';
 import articleSetPricesBySku from './store/article/setPricesBySku.js';
 import articleSetEansBySku from './store/article/setEansBySku.js';
@@ -95,6 +96,7 @@ export default class LibDashStore {
     this.article = {
       createUnderParent: articleCreateUnderParent(pool),
       getBySku: articleGetBySku(pool),
+      listSearchIndex: articleListSearchIndex(pool),
       updateBySku: articleUpdateBySku(pool),
       setPricesBySku: articleSetPricesBySku(pool),
       setEansBySku: articleSetEansBySku(pool),
diff --git a/src/sql/article.js b/src/sql/article.js
index 903c15a..c7d38f8 100644
--- a/src/sql/article.js
+++ b/src/sql/article.js
@@ -160,6 +160,46 @@ FROM brand
 WHERE id = @brandId AND company_id = @companyId
 `;
 
+/**
+ * Company-wide article search index.
+ * Returns one row per article with id, sku, name, and all eans as a JSON array.
+ * Used by the client for local search / autocomplete.
+ */
+export const SEARCH_ARTICLES = `
+;WITH category_tree AS (
+    SELECT id
+    FROM category
+    WHERE id = @rootCategoryId
+
+    UNION ALL
+
+    SELECT c.id
+    FROM category c
+    INNER JOIN category_tree ct ON c.parent_id = ct.id
+)
+SELECT
+    a.id,
+    a.sku,
+    at.name,
+    (
+        SELECT ae.ean
+        FROM articleean ae
+        WHERE ae.article_id = a.id
+        ORDER BY ae.ean
+        FOR JSON PATH
+    ) AS eansJson
+FROM article a
+LEFT JOIN articletext at
+    ON at.article_id = a.id AND at.language_id = @languageId
+WHERE EXISTS (
+    SELECT 1
+    FROM categoryarticle ca
+    INNER JOIN category_tree ct ON ct.id = ca.category_id
+    WHERE ca.article_id = a.id
+)
+ORDER BY a.id
+`;
+
 /**
  * Single-query replacement for resolveArticleBySku + queryBySku.
  * Resolves SKU → article + company + auth, then loads full article detail
diff --git a/src/store/article/listSearchIndex.js b/src/store/article/listSearchIndex.js
new file mode 100644
index 0000000..7d37835
--- /dev/null
+++ b/src/store/article/listSearchIndex.js
@@ -0,0 +1,23 @@
+import { SEARCH_ARTICLES } from '../../sql/article.js';
+import resolveCompanyAccess from '../companyuser/resolveCompanyAccess.js';
+
+export default function listSearchIndex(pool) {
+  const access = resolveCompanyAccess(pool);
+
+  return async (googleAuthId, companyId) => {
+    const { rootCategoryId, languageId } = await access(googleAuthId, companyId);
+
+    const result = await pool
+      .request()
+      .input('rootCategoryId', rootCategoryId)
+      .input('languageId', languageId)
+      .query(SEARCH_ARTICLES);
+
+    return result.recordset.map((row) => ({
+      id: row.id,
+      sku: row.sku,
+      name: row.name,
+      eans: row.eansJson ? JSON.parse(row.eansJson).map((r) => r.ean) : [],
+    }));
+  };
+}