diff --git a/src/store/article/toggleFather.js b/src/store/article/toggleFather.js
index 32210bd..5b80a1f 100644
--- a/src/store/article/toggleFather.js
+++ b/src/store/article/toggleFather.js
@@ -54,8 +54,16 @@ export default function toggleFather(provider) {
         }
 
         const stockRes = await runner.query(
-          'SELECT COALESCE(SUM(l.amount), 0) AS totalStock FROM ledger l WHERE l.article_id = @articleId',
-          { articleId },
+          `SELECT COALESCE(SUM(l.amount), 0) AS totalStock
+           FROM ledger l
+           INNER JOIN manifestarticle ma ON ma.id = l.manifestarticle_id
+           INNER JOIN manifest m ON m.id = ma.manifest_id
+           WHERE m.company_id = @companyId
+             AND (
+               ma.sku = @sku
+               OR ma.sku IN (SELECT asup.sku FROM articlesupplier asup WHERE asup.article_id = @articleId)
+             )`,
+          { companyId, sku, articleId },
         );
         const totalStock = Number(stockRes.rows[0]?.totalStock ?? 0);
         if (totalStock !== 0) {
diff --git a/src/store/articlelist/setItemsByArticleSku.js b/src/store/articlelist/setItemsByArticleSku.js
index ec863f7..847382f 100644
--- a/src/store/articlelist/setItemsByArticleSku.js
+++ b/src/store/articlelist/setItemsByArticleSku.js
@@ -4,6 +4,39 @@ import resolveArticleBySku from '../article/resolveArticleBySku.js';
 import getItemsByArticleSku from './getItemsByArticleSku.js';
 import makeRunner from '../runner.js';
 
+async function hasArticlelistCycle(runner, rootArticleId, candidateComponentId) {
+  const visited = new Set();
+  const queue = [candidateComponentId];
+
+  while (queue.length > 0) {
+    const currentId = queue.shift();
+    if (currentId === rootArticleId) {
+      return true;
+    }
+    if (visited.has(currentId)) continue;
+    visited.add(currentId);
+
+    const res = await runner.query(
+      `SELECT ala.article_id
+       FROM article a
+       INNER JOIN articlelistarticle ala ON ala.articlelist_id = a.articlelist_id
+       WHERE a.id = @currentId`,
+      { currentId },
+    );
+
+    for (const row of res.rows) {
+      if (row.article_id === rootArticleId) {
+        return true;
+      }
+      if (!visited.has(row.article_id)) {
+        queue.push(row.article_id);
+      }
+    }
+  }
+
+  return false;
+}
+
 export default function setItemsByArticleSku(provider) {
   const resolve = resolveArticleBySku(provider);
   const getItems = getItemsByArticleSku(provider);
@@ -75,8 +108,8 @@ export default function setItemsByArticleSku(provider) {
           throw new Error(`Item at index ${i} must specify a valid articleId or sku`);
         }
 
-        if (itemArticleId === articleId) {
-          throw new Error('A Stückliste article cannot contain itself');
+        if (itemArticleId === articleId || await hasArticlelistCycle(runner, articleId, itemArticleId)) {
+          throw new Error('A Stückliste article cannot contain itself or form a circular reference');
         }
 
         if (seenArticleIds.has(itemArticleId)) {
@@ -93,7 +126,16 @@ export default function setItemsByArticleSku(provider) {
           throw new Error(`Article not found for component: ${itemArticleId}`);
         }
 
-        const count = item?.count != null && Number(item.count) > 0 ? Number(item.count) : 1;
+        const rawCount = item?.count;
+        if (
+          typeof rawCount !== 'number' ||
+          !Number.isInteger(rawCount) ||
+          rawCount <= 0 ||
+          rawCount > 2147483647
+        ) {
+          throw new Error(`Invalid count for Stückliste item at index ${i}: must be a positive integer`);
+        }
+        const count = rawCount;
         let sort = item?.sort != null && Number.isInteger(Number(item.sort)) ? Number(item.sort) : i;
 
         while (seenSorts.has(sort)) {
diff --git a/src/store/optionslist/setOptionsByArticleSku.js b/src/store/optionslist/setOptionsByArticleSku.js
index 8e5cb82..f4949f7 100644
--- a/src/store/optionslist/setOptionsByArticleSku.js
+++ b/src/store/optionslist/setOptionsByArticleSku.js
@@ -4,6 +4,39 @@ import resolveArticleBySku from '../article/resolveArticleBySku.js';
 import getOptionsByArticleSku from './getOptionsByArticleSku.js';
 import makeRunner from '../runner.js';
 
+async function hasOptionslistCycle(runner, rootArticleId, candidateOptionId) {
+  const visited = new Set();
+  const queue = [candidateOptionId];
+
+  while (queue.length > 0) {
+    const currentId = queue.shift();
+    if (currentId === rootArticleId) {
+      return true;
+    }
+    if (visited.has(currentId)) continue;
+    visited.add(currentId);
+
+    const res = await runner.query(
+      `SELECT ola.article_id
+       FROM article a
+       INNER JOIN optionslistarticle ola ON ola.optionslist_id = a.optionslist_id
+       WHERE a.id = @currentId`,
+      { currentId },
+    );
+
+    for (const row of res.rows) {
+      if (row.article_id === rootArticleId) {
+        return true;
+      }
+      if (!visited.has(row.article_id)) {
+        queue.push(row.article_id);
+      }
+    }
+  }
+
+  return false;
+}
+
 export default function setOptionsByArticleSku(provider) {
   const resolve = resolveArticleBySku(provider);
   const getOptions = getOptionsByArticleSku(provider);
@@ -75,8 +108,8 @@ export default function setOptionsByArticleSku(provider) {
           throw new Error(`Option at index ${i} must specify a valid articleId or sku`);
         }
 
-        if (itemArticleId === articleId) {
-          throw new Error('An article cannot have itself as an option');
+        if (itemArticleId === articleId || await hasOptionslistCycle(runner, articleId, itemArticleId)) {
+          throw new Error('An article cannot have itself as an option or form a circular reference in options');
         }
 
         if (seenArticleIds.has(itemArticleId)) {
@@ -93,7 +126,16 @@ export default function setOptionsByArticleSku(provider) {
           throw new Error(`Article not found for option: ${itemArticleId}`);
         }
 
-        const count = item?.count != null && Number(item.count) > 0 ? Number(item.count) : 1;
+        const rawCount = item?.count;
+        if (
+          typeof rawCount !== 'number' ||
+          !Number.isInteger(rawCount) ||
+          rawCount <= 0 ||
+          rawCount > 2147483647
+        ) {
+          throw new Error(`Invalid count for options item at index ${i}: must be a positive integer`);
+        }
+        const count = rawCount;
         let sort = item?.sort != null && Number.isInteger(Number(item.sort)) ? Number(item.sort) : i;
 
         while (seenSorts.has(sort)) {