How to Apply Negative Keywords and Brand Exclusions in Performance Max and AI Max

To apply negative keywords to a Performance Max campaign in Google Ads, go to Keywords in the Campaigns menu, open the Negative keywords tab, click the plus button, select the campaign, then add terms one per line or pick an existing negative keyword list. That path is from Google Ads Help, which adds that you set match type with the usual symbols.

Our position, after reading Google's help pages on October 7, 2026: brand terms belong in brand lists, negative keywords are for irrelevant and unsafe queries, and every block should sit at the narrowest scope that does the job. Google allows 10,000 negatives on one campaign, and we would treat that as a ceiling to stay well under, since the same pages warn more than once that exclusions can cost reach and conversions.

Which controls does Performance Max have, and what are the limits?

Google Ads gives Performance Max negative keywords at three scopes (the campaign, a shared list and the account) and brand exclusions at one, the campaign. A Search campaign running AI Max adds a fifth place where a brand list can sit.

The numeric limits are on the account limits page of Google Ads Help. The account-level path and its 1,000 cap are on the account-level negative keywords page of Google Ads Help; that single list applies automatically to search and shopping inventory in Search, Performance Max, App, Shopping, Smart and Local campaigns. We found no statement on whether keywords inside an attached list count toward the 10,000 per campaign.

What negative keywords cannot do in Performance Max

The first gap is inventory. Google's wording is: "Performance Max negative keywords are applicable to Search and Shopping inventory only." For Display and Video, the Performance Max search terms report page in Google Ads Help sends you to excluded content keywords in the Content Suitability center.

The second gap is matching. The account-level page says negative keywords will not match close variants or other expansions: the negative broad match keyword flowers stops an ad for the search red flowers, yet the ad can still serve for red flower. Apply that to a brand name and its plural forms, synonyms and other-script spellings stay open until someone types them in. Misspellings are less settled. The general negative keywords page in Google Ads Help says, in a passage about Search campaigns, that negatives "automatically account for casing and misspellings", while the Performance Max Q&A quoted next says brand exclusions, unlike negative keywords, help block clear misspellings.

Google's advice on brand traffic is clear either way. Its Performance Max Q&A in Google Ads Help says campaign-level brand exclusions help block clear misspellings and foreign-script spellings of a brand, and calls them "often the better option for blocking brand traffic."

Scope is the other half of the decision. The Q&A notes that account negatives also stop those queries in your other campaigns, so your own brand name entered there would block your brand Search campaign along with Performance Max. Keep the account list for terms no campaign should ever serve on.

How do brand exclusions work in Performance Max?

Brand exclusions in Google Ads Performance Max work through brand lists: you build a list of brands, attach it to the campaign as an exclusion, and the campaign stops serving for queries associated with those brands. For an existing campaign, the brand exclusions page in Google Ads Help gives the path as Campaigns, the Settings tab, the campaign, Additional settings, then Brand exclusions.

The same page has a checkbox labeled "Allow Shopping ads on searches that mention excluded brands". Tick it and Shopping ads keep serving on brand searches while the exclusion still applies to text ads, a setup the Q&A describes for retail advertisers who manage brand text ads in a different campaign.

Three details decide how well the exclusion holds:

• Inventory. The brand exclusions page says they "apply to only Search, Shopping, and YouTube search inventory", while the brand settings overview in Google Ads Help names Search and Shopping. Other Performance Max inventory sits outside the control on either reading.
• Matching. The Q&A cautions that traffic mentioning the words in a brand name "will only be blocked if they clearly refer to the brand."
• List coverage. The overview says brand names with no word in common (its example is Google, YouTube and Alphabet) each need adding. If a brand is missing, the Q&A says Google Ads shows an option to request it.

The reason to bother is measurement. A Performance Max campaign that serves on your own name counts those conversions in its ROAS, and the Q&A presents own-brand exclusion as a way to get a clearer view of the campaign's prospecting potential. Whether those brand clicks were incremental is a separate question that no exclusion setting answers.

How do you apply brand exclusions in AI Max for Search campaigns?

To apply brand exclusions in Google's AI Max for Search campaigns, use the brand exclusions setting inside the AI Max panel: open Campaign settings, select AI Max in the section menu, scroll to the Brands section and add brand lists to the exclusions entry. The setup page in Google Ads Help describes AI Max as "an optimization layer within existing Search campaigns", so there is no new campaign to build. Brand exclusions there are a campaign-level control, while brand inclusions can be set for the campaign or for an ad group, and an ad group's inclusions override the campaign's for that ad group only.

The setting has moved. According to the brand exclusions page, brand exclusions for Search campaigns were set to begin upgrading into AI Max starting May 27, 2025. Advertisers new to them have to turn on AI Max to reach the brand settings panel, while campaigns that already had exclusions can leave them working outside AI Max, though attaching a new brand list requires AI Max. The page adds: "This change does not impact Performance Max campaigns."

Do negative keywords and brand controls still apply once AI Max is on?

In Google Ads, AI Max negative keywords and brand exclusions both apply as controls on the expanded matching, though they depend on different switches. On negatives, the AI Max FAQ in Google Ads Help is direct: "Negative keywords will be respected even with AI Max turned on." Brand settings behave differently. The same FAQ says turning AI Max off disables every AI Max feature, with the example that a campaign running brand exclusions will have them disabled, and that turning it back on restores the settings as they were. A brand exclusion in the AI Max panel therefore lasts only while the toggle stays on, which is worth knowing before anyone pauses AI Max for a test.

Brand exclusions or brand inclusions?

Brand exclusions vs brand limits in Google Ads PMax is a short comparison, because Performance Max only has the exclusion. The setting that limits a campaign to chosen brands is called brand inclusions, and the brand settings overview lists it as available for Search campaigns, where the campaign "will only serve for queries associated with the brands you select". We found no setting named brand limits on the pages we read; the numeric limits on brand lists are in the first table.

When a campaign carries both, the overview settles it: "Brand exclusions will be prioritized over brand inclusions." It also warns that brand settings limit a campaign's reach and that performance may decrease, which matters if you are trying to scale paid ads without losing ROAS.

Which reports show a block is holding?

For Performance Max, open the Search terms report in the Campaigns menu and choose the view named "Search terms and landing pages for Performance Max", then search it for the blocked term or brand. The Ad format segment separates Shopping ads from Text ads, which the report page says can help you analyze format-level brand exclusions; with the Shopping checkbox ticked, our expectation is brand queries against Shopping ads and none against Text ads.

For a Search campaign with AI Max, the reporting page in Google Ads Help says to add the Source column to the search terms report and filter Match type for "AI Max". It cautions that this filter may show lower numbers because it does not consider "Other search terms", so an empty filtered view is weaker proof than it looks. Google also advises waiting at least 2 weeks after enabling AI Max before making changes such as adding negative keywords.

Once the blocks hold, the campaign's numbers describe a different mix of queries, so judge it against prospecting targets such as CAC and rerun the break-even figures; our ROAS calculator and paid media team are further resources for that. We would rather inherit an account with a short negative list and two tidy brand lists than one with thousands of negatives nobody can explain.

Sources

• Google Ads Help: Negative keywords in Performance Max campaigns
• Google Ads Help: About your Google Ads account limits
• Google Ads Help: About account-level negative keywords
• Google Ads Help: About the search terms report in Performance Max
• Google Ads Help: Answering Your Top Questions About Performance Max
• Google Ads Help: Apply brand exclusions to Performance Max or Search campaigns
• Google Ads Help: About brand settings for Search and Performance Max
• Google Ads Help: Set up AI Max for Search campaigns
• Google Ads Help: Frequently asked questions about AI Max for Search campaigns
• Google Ads Help: About reporting in AI Max for Search campaigns
• Google Ads Help: About negative keywords