The Search Partner Network (SPN) is the set of websites and apps outside Google's own search pages that display Google search ads. Google Ads Help describes search partners as "sites in the Search Network that partner with Google to show ads," extending the reach of search ads "to hundreds of non-Google websites, as well as YouTube." It exists because sites running their own search boxes need a way to monetise them, and Google has more advertiser demand than its own queries absorb. Google supplies the ads, the partner supplies the page and query, and the two split the revenue.

The network is a subset of the Google Search Network, not a separate product. It arrives bundled with Search, Shopping, App and Performance Max campaigns unless switched off or capped.

How partner traffic is sourced

Most partner inventory comes from AdSense for Search (AFS), the publisher product that lets a site place Google text ads beside its own results. Court documents in the US government's antitrust case named ask.com, startpage.com, web.de, ebay.com and bestbuy.com as partners, as PPC Land reported when placement reporting arrived. The syndication explainer covers the publisher side in detail.

The mechanics run in a fixed order. A visitor types a query into a partner's search box, or lands on a partner page that shows "related searches." The partner sends Google an ad request containing its account identifier, the query, styling instructions and the maximum number of ads it will show. Google runs the query through the same keyword matching used on Google Search, so an exact, phrase or broad match keyword can trigger an ad on a partner page just as it would on google.com. Eligible ads are ranked, and the winners are returned for display "alongside, above, within, or below search results," on site directory pages, product detail pages and, according to Google, YouTube search results and Watch pages.

Pricing is cost per click (CPC), so the advertiser pays only when someone clicks. Since July 2023, according to Google's SPN announcements page, partner traffic in manually bid campaigns has been priced by one of two systems. Smart Pricing applies when a campaign has no conversion tracking or very little conversion data and lowers bids to limit overspending on traffic that "may convert poorly." Smart Bidding applies when conversion data is sufficient and aims for a cost per conversion similar to Google Search. In February 2025 Google said it had further tuned Target CPA and Target ROAS for partner traffic.

A second route into the network is less visible. Some AFS publishers buy traffic elsewhere, from social platforms, native ad networks or affiliates, and land visitors on "related search" pages that then show Google ads. Google requires these publishers to pass the text of the upstream ad in a field called referrerAdCreative. From November 1, 2025, omitting it became a policy violation under AdSense for Search rules.

Controls by campaign type

In a Search campaign, the Networks section carries a checkbox labelled "Include Google search partners," switched on by default. Unticking it removes the network entirely. Shopping campaigns have an equivalent option. Reporting splits the two through the Network segment, which separates "Google search" from "Search partners."

Performance Max gave no such choice for most of its life. Search partners were bundled with Google Search, YouTube, Display and other surfaces, and advertisers could only exclude individual placements. In January 2026 Google added a search partner split to Performance Max channel reporting for all accounts. A "Partners Alfa" checkbox was spotted inside Performance Max on April 30, 2026, and a Google spokesperson later confirmed it was a pilot limited to selected advertisers.

The broader change came on October 14, 2026, when Google announced channel prioritization and budget allocation, allowing advertisers to limit partner spend by percentage. Low-priority channels receive budget only after high-priority ones and can be capped at a share of the average daily budget. In Search campaigns, Google Search, search partners and the Display Network can each be ranked; in Performance Max, search partners and Display are the two adjustable channels. Ginny Marvin, Google's Ads Product Liaison, said Performance Max advertisers can set search partner allocation to 0%. Google's help page calls the allocations targets the system "will aim to" respect, adding "this isn't a guarantee."

Origin and evolution

On May 1, 2002, AOL chose Google to supply search results and paid listings across AOL, CompuServe and Netscape, replacing Overture. AdSense followed in 2003, and its search product formalised syndication to smaller sites. A parked-domain product, AdSense for Domains, became available to all US publishers in December 2008, according to TechCrunch, which mattered later: parked pages became one of the most criticised parts of the network.

For two decades the network was largely opaque. Advertisers could see aggregate partner clicks and costs but not which sites served them. That changed after November 2023, when Adalytics, a research firm led by Krzysztof Franaszek, published a report alleging that Google served major brands' search ads on inappropriate and sanctioned websites through search partners. Adalytics estimated the network generates about $10.5 billion a year for Google and said it had found Google's search embed code on more than 80,000 sites, over 20,000 of them parked domains. Dan Taylor, a Google Ads vice president, disputed the findings. According to a December 2023 update from the World Federation of Advertisers (WFA), Google said "over 90% of Search Partner Network impressions are from Top 100 sites and apps (including YouTube)," and that policy-violating sites represented 0.002% of impressions.

In February 2025 Google began switching parked domains off by default. In April 2025 it introduced a pre-screening option built on exclusion lists from DoubleVerify, Integral Ad Science (IAS) and Zefr. On August 19, 2025 it released full placement reporting for Search, Shopping and App campaigns, listing each partner site with impressions. Parked domains ceased to be an ad surface on February 10, 2026, and in April 2026 Google added an Invalid Activity Credit Report showing refunded invalid-traffic spend by campaign.

Why it matters for marketers

The network is on by default, and defaults move money. Advertisers who never open the Networks setting buy partner inventory without choosing it, and whether it adds value is unsettled.

Google's position is that it does. In December 2025 the company said advertisers spending at least 5% of their budget on search partners, in campaigns not limited by budget, typically saw 11% more conversions with volume-focused Smart Bidding and 7% more conversion value with value-focused strategies. Independent analysis points the other way. Intelligency Group found in June 2025 that partner placements delivered 37% lower return on ad spend (ROAS) than Google Search. Neither figure has been audited by a third party.

Jyll Saskin Gales, a former Google employee who now coaches advertisers, said in October 2025 that "this inventory is all trash - as we can now see from the new content reporting," and that with Smart Bidding and sound conversion tracking, partner spend falls to zero or near zero.

Limitations and disputes

The size of the network remains contested. Google's documentation says "hundreds" of sites; Adalytics counted more than 80,000 carrying Google's code. Both can hold if a few large partners carry most impressions, as Google's 90% figure implies, but no public reconciliation exists.

Reporting is still partial. Placement reports for Search campaigns show impressions by site, and Mike Ryan, a retail search specialist, noted at launch that this was "impression data only." Advertisers can exclude sites they see, but only after ads have run on them.

Automation complicates control. When Google launched AI Max for Search, which expands matching beyond the keyword list, early testers saw heavy partner delivery. Ryan called the extent to which AI Max was "expansionary on SPN" "deeply disturbing," adding that "the best defense of SPN is that intent is SO low, it doesn't generate clicks," as PPC Land reported in August 2025.

The new budget controls carry their own caveats. Google's help page and Marvin's public answers disagree on shared budgets, experiments and API availability, and the caps are described as best-effort rather than enforced.

Commonly confused terms

The Google Search Network is the larger pool: Google Search, Shopping, Images, Maps and AI surfaces, plus search partners. Opting out of partners leaves the Search Network in place.

The Google Display Network sells content-page placements targeted by audience or context, not by a query. Search campaigns reach it only through Display expansion, a separate checkbox.

AdSense for Search is the supply side of the same transaction. Publishers use AFS; advertisers see the result as search partners.

Microsoft Advertising runs its own search partners, historically called syndicated search partners, on sites such as Ask.com and Forbes. According to Microsoft support documentation, partners meeting quality thresholds moved into a "Microsoft sites and select traffic" tier, including Yahoo.com and reported in aggregate; the rest are reported by domain and can be excluded. Google Partners, an agency certification programme, is unrelated.

Recent developments

October 2026 changed how much of the network advertisers must accept. Channel prioritization began rolling out progressively on October 15, and Marvin answered questions in her October 16 newsletter, saying existing opt-outs and placement exclusions are unchanged and that "these are budgeting controls and not bidding controls."

The network's legal position is unresolved. On September 2, 2025, Judge Amit Mehta ordered Google to syndicate search results and search text ads to qualified competitors under five-year licences, a remedy Google appealed in January 2026. As of October 2026, the appeals court has not ruled.

Timeline

  • May 1, 2002: AOL selects Google for search results and paid listings across AOL, CompuServe and Netscape
  • 2003: AdSense launches, extending Google ads to third-party publishers
  • December 2008: AdSense for Domains becomes available to all US publishers
  • July 2023: Smart Pricing and Smart Bidding applied to manually bid search partner traffic
  • November 2023: Adalytics alleges brand ads ran on inappropriate and sanctioned sites via search partners
  • December 2023: WFA publishes Google's response citing 90% of impressions from top 100 partners
  • February 2025: Google starts defaulting parked domains off; Smart Bidding tuned for partner traffic
  • April 2025: Pre-screening lists from DoubleVerify, IAS and Zefr introduced
  • June 2025: Intelligency Group reports 37% lower ROAS on search partners
  • August 19, 2025: Full placement reporting for Search, Shopping and App campaigns
  • September 2, 2025: Judge Mehta orders syndication of search results and search text ads to qualified competitors
  • November 1, 2025: Referrer Ad Creative requirements enforced for AFS publishers
  • December 2025: Google publishes 11% and 7% uplift claims for partner spend
  • January 2026: Search partner split added to Performance Max channel reporting
  • February 10, 2026: Parked domains removed from the network
  • April 2026: Invalid Activity Credit Report launched
  • April 30, 2026: Performance Max partner checkbox spotted in alpha
  • July 28, 2026: Google confirms the Performance Max pilot is limited
  • October 14, 2026: Channel prioritization and budget allocation announced
  • October 15, 2026: Progressive rollout of the new controls begins

Summary

Who. Google operates the network and its auctions; partner publishers such as Ask.com, Startpage, web.de and eBay supply the pages, mostly through AdSense for Search; advertisers buy it through Google Ads and Search Ads 360. Microsoft runs a parallel partner network.

What. A pool of non-Google sites and apps, plus YouTube search, that show Google search ads triggered by queries, priced per click and included by default in most search-led campaign types.

When. The partner model dates from the AOL deal of May 2002. Scrutiny peaked after the November 2023 Adalytics report, and placement reporting (August 2025), parked-domain removal (February 10, 2026) and percentage spend caps (announced October 14, 2026) followed.

Where. On partner search results pages, related-search pages, directory and product pages, and YouTube, in every market where Google Ads operates.

Why. Partners extend reach beyond Google's own queries and give publishers revenue from search boxes. Disputed quality, conflicting performance data and a court-ordered syndication remedy keep the network contested.