Fixing “Duplicate ID” errors in your product feed

What Google is actually complaining about

The id attribute is the primary key of your feed. When two rows share one, Google doesn't merge them — it keeps whichever it saw last and silently drops the other. Products disappear from Shopping without ever showing a red error, which is what makes this one so expensive.

Where duplicates come from:

• Variants sharing a parent SKU. Every size and colour needs its own id; the shared value goes in item_group_id.
• The same product in two collections, exported once per collection by the feed app.
• Case and whitespace collisions — sku-4471, SKU-4471 and SKU-4471  are treated as the same ID.
• Recycled IDs from discontinued products, which inherit the dead item's history.

How to fix it

1. Sort by id and find collisions — after trimming whitespace and lowercasing, or you'll miss half of them.
2. Give each variant a unique suffix: SKU-4471-RED-M.
3. Set item_group_id to the shared parent SKU on every variant so Google still groups them correctly.
4. De-duplicate rows that are genuinely the same product exported twice.
5. Keep IDs stable forever. Changing an id resets that product's performance history and it re-enters review.

What a correct row looks like

id,item_group_id,title,size,color,price
SKU-4471-RED-M,SKU-4471,Canvas Jacket,M,Red,89.00 USD
SKU-4471-RED-L,SKU-4471,Canvas Jacket,L,Red,89.00 USD
SKU-4471-BLU-M,SKU-4471,Canvas Jacket,M,Blue,89.00 USD

How long until the disapproval clears

Merchant Center re-crawls a scheduled feed on its normal cadence, so a fix can sit invisible for up to 24 hours. To force it: Products → Feeds → your feed → Fetch now, then re-check Diagnostics the following day. Items usually flip back to Active within one or two crawls once the attribute validates.

Other common disapproval causes