How to Fix Products Disapproved in Google Merchant Center for Missing GTIN or MPN
Table of Contents
- Introduction
- Understanding GTIN and MPN
- Common GTIN and MPN Errors in Google Merchant Center
- How to Identify GTIN and MPN Issues in Google Merchant Center
- Step-by-Step Guide to Fixing GTIN and MPN Errors
- Best Practices to Avoid GTIN and MPN Errors
- Conclusion
Introduction
Selling on Google Shopping can boost your online sales quickly. But if your product listings are disapproved in Google Merchant Center, your ads stop showing. GTIN or MPN errors are among the most frequent grounds for rejection. These are product identifiers that help Google understand what you’re selling.
Similar to an EAN or UPC, a GTIN (Global Trade Item Number) is a unique code. It is used by manufacturers to track products. When a product lacks a GTIN, it is identified by its Manufacturer Part Number, or MPN. Both are important for accurate product listings in Google Shopping.
When these identifiers are missing or wrong, Google can’t match your products to its catalog. This results in disapprovals, lower visibility, and lost revenue. Your products won’t appear in shopping ads, even if everything else is correct.
If you’re using WooCommerce or any shopping platform, fixing these errors is critical. Google’s system checks your product feed regularly. A single issue can affect many listings in your account.
Here’s what usually happens when GTIN or MPN issues occur:
- Google Merchant Center shows a warning or disapproval message.
- Your product gets removed from Google Shopping ads.
- You may see fewer impressions or zero clicks on your listings.
This guide will take you step-by-step through the entire process. You’ll learn what GTIN and MPN mean, why Google needs them, how to spot errors in your Shopping feed, and how to fix them correctly.
Understanding GTIN and MPN
Before fixing the errors in Google Merchant Center, it’s important to understand what GTIN and MPN actually mean. These are key product identifiers that help Google know exactly what you’re selling.
What is GTIN?
GTIN stands for Global Trade Item Number. The manufacturer assigns a unique code to each product. Google uses GTIN to match your goods to other products in its database. This improves ad visibility and search accuracy.
Common GTIN types include:
- UPC (used mainly in the USA)
- EAN (used in Europe)
- ISBN (used for books)
- JAN (used in Japan)
You can usually find the GTIN on the product’s packaging, barcode label, or manufacturer’s listing.
If you sell branded products, GTIN is usually required. Google expects this code for most new items. Without it, your product may not show in Shopping results.
What is MPN?
MPN stands for Manufacturer Part Number. It is applied when a product lacks a GTIN. It’s often required for custom or handmade items, private-label products, or those from smaller brands.
MPNs help identify a product model or version. They are not universal like GTINs but still give Google a way to group similar items.
You must include MPN if:
- The item is either custom-made or unbranded.
- The product doesn’t have a GTIN
- The brand is not well-known or listed in global databases
If you leave MPN blank in these cases, Google may disapprove the product.
Why Google Requires GTIN or MPN
Google uses GTINs and MPNs to connect your products with their internal product catalog. This helps:
- Improve product matching and relevance in searches
- Display rich product info like reviews and pricing
- Compare your prices with competitors
Without correct identifiers, your product may:
- Show up in the incorrect category
- Be viewed by the incorrect audience
- Or not appear at all
So, if you’re serious about selling on Google Shopping, adding correct GTIN or MPN is a must.
Common GTIN and MPN Errors in Google Merchant Center
Errors related to GTIN and MPN are among the most frequent issues in Google Merchant Center. These errors can lead to product disapprovals, meaning your products won’t show in Shopping ads. The first step in correcting these mistakes is understanding them.
Let’s explore each error in detail.
- Missing GTIN
This is the most common issue. It happens when Google expects a GTIN for a product, but it’s not provided in your product feed.
You’ll likely see a warning like “Missing GTIN” or “Missing required attribute: GTIN” in the diagnostics tab.
This typically occurs when:
- You sell branded products but skip adding the barcode.
- You’re unaware of GTIN requirements for your category.
- Your product feed plugin is not sending GTIN data.
If your product is new and sold by a popular brand, Google expects it to include a valid GTIN. Without it, your product may be disapproved or perform poorly in search.
- Invalid GTIN
Sometimes, a GTIN is included but in the wrong format or invalid. This error appears as “Invalid GTIN” or “Incorrect value [gtin]” in the Merchant Center.
This happens when:
- The GTIN is not 8, 12, 13, or 14 digits long.
- The GTIN is randomly made up or not recognized by Google.
- Several unrelated items use the same GTIN.
An invalid GTIN prevents Google from matching your product with the correct item in their catalog.
- Missing MPN for Custom Products
MPN is required when GTIN is not provided, especially for custom or unbranded products. If you skip both GTIN and MPN, Google flags the product.
You might see “Missing MPN” or “Missing required attribute: MPN” errors.
This is common for:
- Handmade items
- White-label products
- Products from smaller manufacturers
Even if the item doesn’t have a GTIN, providing an MPN helps identify it.
- Incorrect Use of identifier_exists
Google allows you to use the attribute identifier_exists to tell them whether GTIN or MPN applies. But misusing this can trigger errors.
Examples of misuse:
- Setting identifier_exists to FALSE when the product actually has a GTIN
- Setting it to TRUE but not including a GTIN or MPN
This confuses Google’s system and may lead to disapproval.
How to Identify GTIN and MPN Issues in Google Merchant Center
Before you can fix any product identifier errors, you need to find them. Google Merchant Center makes this process simple if you know where to look. It provides detailed insights into your product feed and lists all current issues.
Step 1: Log in to Google Merchant Center
Go to your Google Merchant Center account and log in first. To gain access, use the primary admin email. Once you’re in, you’ll land on the account overview page.
Step 2: Go to the Diagnostics Tab
On the left sidebar, click “Products” and then choose “Diagnostics.” This tab shows the health of your product listings.
Here, you’ll see three sections:
- Account issues
- Feed issues
- Item issues
Focus on Item issues for GTIN and MPN problems. Specific errors for each impacted product are listed in this section.
Step 3: Find GTIN and MPN Related Warnings
Scroll through the item issues and look for messages like:
- Missing GTIN
- Invalid GTIN
- Missing MPN
- Incorrect value [gtin]
- Missing or invalid unique product identifiers
Click on each issue to view how many products are affected. A report in CSV format is also available for download and perusal.
Step 4: Review the Product Details
Clicking on the issue will show you sample products with errors. Each listing will show:
- Product title
- ID
- Last crawl date
- Affected attribute (e.g., GTIN or MPN)
This helps you pinpoint where the problem is coming from—your store, the feed file, or a plugin.
Step 5: Check Feed Rules or Plugins
If you’re using WooCommerce or another platform, review your feed settings. Some plugins may not send GTIN or MPN by default. You’ll need to manually map product identifiers in those cases.
Step-by-Step Guide to Fixing GTIN and MPN Errors
The next step is to correct the mistakes that have been found in your Google Merchant Center account. Whether the issue is a missing GTIN, an invalid one, or a missing MPN, correcting these will help get your products reapproved and back into Google Shopping results.
This comprehensive tutorial will assist you in effectively resolving these problems.
Step 1: Verify Your Product’s GTIN or MPN
Start by checking the actual product data. Many times, the error comes from incorrect or missing values added during the upload process.
Here’s how to verify GTIN:
- Check the product packaging or barcode label.
- Look for a UPC, EAN, or ISBN (usually 12 or 13 digits).
- Refer to the official GS1 database (https://www.gs1.org/).
To verify MPN:
- Visit the manufacturer’s website.
- Look for the model or part number under product details.
- Check invoices or supplier listings.
If the product has no GTIN, ensure it has a correct MPN and brand name.
Step 2: Update Product Information in Your Source Platform
If you’re using WooCommerce or another shopping cart platform, log in to your store’s admin dashboard.
Update the GTIN or MPN fields in the product data. Depending on your plugin or feed tool, these fields may be named differently.
Common fields include:
- GTIN
- UPC
- EAN
- MPN
- Brand
- Identifier Exists
If your theme or plugin doesn’t support these fields, consider installing a product feed manager plugin.
Among the often used tools are:
- Product Feed PRO for WooCommerce
- CTX Feed – WooCommerce Product Feed Manager
These tools allow you to map the correct product attributes and include them in your Google Shopping feed.
Step 3: Correct the identifier_exists Attribute
The identifier_exists attribute tells Google whether a product has a GTIN or MPN.
Here’s how to use it properly:
- Set to “true” if the product has a GTIN or MPN.
- Set to “false” only if it genuinely has no identifier.
Don’t set it to “false” to bypass errors unless it’s a custom or handmade item. Google flags misuse of this attribute and may suspend your feed.
In your feed plugin or custom feed file, make sure this value is mapped correctly.
Step 4: Regenerate and Resubmit Your Product Feed
After updating the product data, regenerate your Google Shopping feed. Most WooCommerce feed plugins allow you to do this with one click.
Then, go back to Google Merchant Center:
- Go to Products > Feeds.
- Click on your primary feed name.
- Hit the “Fetch Now” button to pull the latest data.
This action prompts Google to reprocess your product listings. It could take several hours for the adjustments to take effect, depending on how many products there are.
Step 5: Request a Manual Review (If Needed)
Once you’ve fixed the issues and updated your feed, most disapprovals will automatically resolve during the next review cycle.
However, if errors persist, you can request a manual review.
To do this:
- Navigate to the Diagnostics area.
- Find the error message related to GTIN or MPN.
- If the option appears, click “Request Review.”
Google will manually check the product again. It typically takes 24 to 48 hours to complete this operation.
Step 6: Monitor the Status Regularly
Fixing errors is not a one-time job. You should monitor your feed regularly to make sure new products don’t face the same issues.
Set a reminder to check the Diagnostics tab weekly. This allows you to spot issues early and prevent widespread product rejections.
You can confidently correct GTIN and MPN mistakes by following these methods. Maintaining accurate product data on Google Shopping increases visibility, clicks, and revenues.
Best Practices to Avoid GTIN and MPN Errors
Correcting MPN and GTIN mistakes is only the first step. Best practices are essential to maintaining the health of your Google Merchant Center account. These steps will help prevent disapprovals in the future and ensure your products remain active in Google Shopping.
Always Collect Product Identifiers Early
When you add new products to your store, always collect their identifiers first. This includes:
- GTIN (UPC, EAN, ISBN)
- MPN (if GTIN is not available)
- Brand name
Get this data directly from the manufacturer or packaging. If you use dropshipping, ask your supplier for this information.
Use Trusted Sources for GTIN Data
Never guess or create random GTINs. Google checks every GTIN against its official database. Invalid codes lead to product disapproval.
Use these safe sources:
- Product packaging
- Manufacturer websites
- GS1 database
Avoid fake GTIN generators or placeholder numbers.
Keep Product Feeds Updated
Update your product feed regularly, especially when:
- You add new items
- You change product details
- You switch suppliers
Using a feed plugin with scheduled updates helps keep your data fresh. Most plugins allow automatic daily or weekly syncing with Google Merchant Center.
Validate Feed Before Uploading
Always check your product feed before sending it to Google. Look for:
- Missing GTIN or MPN
- Wrong attribute mapping
- Invalid characters or formatting
Many WooCommerce feed plugins offer a preview or test mode. Use this feature to avoid errors.
Set Up Regular Diagnostics Checks
Develop the practice of checking Merchant Center’s Diagnostics tab once a week. Fixing small issues early prevents large-scale product disapprovals later.
You can enable email notifications to stay informed about new issues instantly.
By following these simple best practices, you’ll save time and avoid repeated disapprovals. It also helps boost your visibility and performance in Google Shopping.
Conclusion
Success in Google Shopping depends on keeping your product stream neat and compliant. Ignoring small errors like missing GTIN or MPN can lead to lost sales and disapproved listings. Staying ahead means acting fast, staying organized, and using the right tools.
If you’re using WooCommerce and want to avoid the hassle of manual fixes, let WooHelpDesk.com do the heavy lifting. With automated feed management, smart error detection, and full support for GTIN and MPN mapping, it’s built to keep your products live and visible.
