A ghost campaign — sometimes called a catch-all campaign, a priority campaign, or a query funnel — is a Google Shopping campaign structure designed to capture and isolate search demand that your main campaigns can't efficiently bid on. The term "ghost" comes from the fact that the queries it captures are often invisible to you in your search terms report, but they're generating impressions and clicks anyway.
Understanding ghost campaigns requires understanding how Google Shopping's priority settings work, and how product feed data interacts with campaign structure to control which campaign wins the auction for any given query.
How Shopping campaign priority works
Google Shopping campaigns have three priority settings: Low, Medium, and High. When the same product is eligible to appear in multiple campaigns, Google uses campaign priority — not bid level — to determine which campaign enters the auction first. High priority campaigns always take precedence over Medium, which always takes precedence over Low, regardless of bids.
This creates an exploitable structure. You can deliberately set up campaigns with different priority levels and different negative keyword lists to route specific search queries to specific campaigns — and therefore to specific bids.
The basic ghost campaign structure
A three-tier ghost campaign structure works like this:
- High priority campaign — Ghost / Catch-all: Very low bid (e.g. £0.05–£0.15). No negative keywords except brand terms. No product group exclusions. This campaign enters the auction for every Shopping query Google considers your products eligible for — including queries you'd never think to bid on and queries that don't appear in your search terms report because they generate fewer than a handful of clicks. Because the bid is very low, you're happy for it to show on ambiguous or low-intent queries, but you don't pay much when it does.
- Medium priority campaign — Category / Generic: Medium bid. Negative keywords added for specific product names and brand + product combinations. This catches category-level queries ("mens wax jacket", "waterproof jacket UK") after the high-priority campaign's low bid loses the auction for specific-product queries that route to the Low priority campaign.
- Low priority campaign — Specific / Brand + Product: Highest bid. Negative keywords added for all generic category terms. Only wins the auction when a highly specific, high-intent query is entered — "Barbour Beaufort jacket navy XL" routes here because the high and medium priority campaigns have negatives for specific brand+product combinations.
The query funnels down through priority levels. Generic queries land in Medium priority at medium bids. Specific, high-intent queries land in Low priority at your highest bids. Unknown or unusual queries land in High priority at minimal bids — you're in the auction but at negligible cost. No query goes uncontested and over-bid simultaneously.
The feed data that makes ghost campaigns work
Ghost campaigns depend entirely on product feed quality. The High priority catch-all campaign is only valuable if your products are eligible for a wide range of queries — which means your titles, descriptions, and google_product_category values need to be specific and complete.
If your product titles are manufacturer descriptions ("BBBEUJNAV-XL") rather than search-optimised titles ("Barbour Beaufort Jacket Men Navy XL"), Google can't match your products to the long tail of queries the ghost campaign is designed to capture. The ghost campaign structure channels queries efficiently — but the feed quality determines how many queries are in the channel in the first place.
In Trajekt, you can set up title optimisation rules that run automatically on every feed refresh: prepend brand, structure key attributes, append relevant terms. This ensures your ghost campaign always has maximum product eligibility across the full query spectrum, not just the obvious head terms.
Negative keyword management across priority levels
The ghost campaign structure is only as clean as your negative keyword lists. The key lists to maintain:
- Brand negatives in High priority: Add all your brand names as negatives in the High priority campaign so that branded queries route directly to Low priority at high bids.
- Category negatives in Low priority: Add all generic category terms as negatives in Low priority so that non-specific queries don't enter the auction at your highest bid.
- Profitability negatives in all tiers: Queries that have generated clicks but zero conversions across all tiers over 90 days should be added as negatives. The ghost structure doesn't exempt you from standard negative keyword hygiene.
The negative keyword lists need regular maintenance as your product range changes and as Google's query matching evolves. Set a calendar reminder monthly to review Search Terms reports across all three campaign tiers and update negatives accordingly.
Custom labels enable bid-by-margin within the ghost structure
The ghost campaign priority structure controls which campaign enters the auction per query. Custom labels in your product feed control which products within each campaign get differentiated bids via product group splits.
The most effective combination: ghost campaign structure for query routing, plus custom label-based product groups for margin-based bidding within each campaign tier. High-margin products in the Low priority campaign get higher bids than low-margin products in the same campaign — even though they share the same query routing logic.
Trajekt sets custom labels automatically via rules: IF margin_tier = high THEN custom_label_0 = "high-margin". These labels apply on every feed refresh, so when your product margins change (seasonal promotions, cost changes), your label-based bids reflect the change automatically without manual campaign edits.
Monitoring the ghost campaign structure
The key metric to watch is impression share distribution across your three campaign tiers. In a healthy ghost structure, the High priority campaign should capture 60–80% of impressions at very low cost. The Medium priority campaign captures 15–25% at medium cost. The Low priority campaign captures 5–15% at high cost — but these are your most specific, highest-converting queries.
If your High priority campaign is capturing most of the spend rather than just most of the impressions, your bid structure is off — the ghost campaign's bid should be low enough that it only wins auctions when nothing else is competing. Adjust the High priority bid downward until spend concentrates in the Medium and Low priority tiers where it belongs.
Trajekt is a UK-built product feed management platform. Our editorial team covers feed optimisation, Google Shopping strategy, ChatGPT commerce, and ecommerce channel management for UK merchants and agencies.