"AI Max" & The Unified Search Engine: Winning in 2026
Scott Welton
June 26, 2026
10
minutes read
Two CMOs running identical AI Max campaigns can produce wildly different results in 2026. This article unpacks why that variance now traces back to decisions made before the campaign goes live, and what the discipline of governing AI-led search actually looks like once Google's September auto-upgrade closes the opt-out window.
On 15 April 2026, Google quietly retired one of the longest-running formats in paid search. Brandon Ervin, Director of Product Management at Google Ads, confirmed that AI Max for Search had moved out of beta and that Dynamic Search Ads, Automatically Created Assets and the campaign-level broad match setting would all auto-upgrade into AI Max from September. Voluntary upgrades begin now. After September, opting out is no longer on the table.
For CMOs and performance leads, this is more than a feature retirement. AI Max stops being a product to evaluate and becomes the default architecture of paid search. By autumn, almost every advertiser will be running it. The 2026 differentiator will be how deliberately each brand governs what runs inside it.
Pic. The AI Max migration window: April to September 2026.
The end of the binary
For most of the last decade, brand and performance lived in different rooms. Brand teams chased reach and equity; performance teams chased conversion. AI Max collapses the wall. With it enabled, a single Search campaign can spend across keyword-anchored intent and AI-generated query expansion, with ads now appearing alongside Google's AI Overviews and AI Mode placements that didn't exist at the start of last year.
Both halves of the architecture only work when each is designed with intent. Manual Search remains the high-intent capture layer; Google's spokesperson confirmed at GA that "keywords remain an essential component of a successful campaign strategy, providing the 'fuel' for our AI." AI Max takes over the catch-all role DSA used to play, surfacing net-new queries the keyword set could never anticipate.
L'Oréal, an early-access partner, reported twice the conversion rate at a 31% lower cost per conversion after activation, including from queries—like "what is the best cream for facial dark spots?"—that no human-built keyword list would have surfaced.
Data is the new creative director
The variance in real-world results tells a more honest story than the launch decks. Smarter Ecommerce's analysis of more than 250 Search accounts running AI Max, reported by Search Engine Land, found a median revenue uplift of 13%—almost identical to Google's own non-retail benchmark—but a median CPA increase of 16% and a ROAS spread that ran from 42% above baseline to 35% below. "Happiness is expectations minus reality," was Mike Ryan's takeaway from running it. Only around a fifth of campaigns held within their original ROAS target.
Pic. AI Max in 250+ Search campaigns: the variance behind the average.
The pattern is not random. Account by account, the gap between strong and weak AI Max performance traces back to the quality of the conversion signals the system has to learn from.
With third-party data continuing to thin, AI Max depends more heavily than its predecessors on first-party inputs: server-side conversion tracking, enhanced conversions, CRM revenue imports and customer-match lists tagged with lifetime-value data.
Google's own year-end report noted a 14% uplift in conversion signals among advertisers who configured the Google tag gateway—a small change to data plumbing that meaningfully changes what the algorithm can see. The strategist's leverage point has moved out of the campaign manager and into the data infrastructure.
Defending against algorithmic cannibalization
The most expensive failure mode in 2026 is internal. Without explicit brand exclusions and a properly maintained negative-keyword list, AI Max will capture branded queries that the keyword Search campaign would have won at much lower CPC, then bank the conversion. Reported ROAS climbs. Incremental customers do not. The trade press has converged on the same diagnosis: a "Power Pack" or hybrid priority structure that treats AI Max, traditional Search, Demand Gen and Performance Max as distinct functions inside one architecture, rather than competing campaigns inside the same auction.
The meaningful difference between AI Max and Performance Max, and the reason this is recoverable, is that AI Max respects negative keywords at both campaign and ad-group level. Account-level negative lists for branded and navigational queries should be in place before AI Max is switched on, not after. High-margin product lines belong in dedicated tiers with their own ROAS targets, not blended into a single campaign that optimizes toward the average. This is the difference between letting the algorithm grade its own homework and giving it a marking rubric.
From operator to architect
The CMO role inside paid search has changed in degree more than in kind. Where the work used to be configuration—bid adjustments, keyword expansion, match-type management—it is increasingly governance.
Outside signals reinforce the point:
AdWeek reported in April that 37% of consumers now begin a search with an AI tool rather than a search engine.
BrightEdge data, published by Search Engine Land, showed Google search impressions up 49% in the year following AI Overviews' launch, with click-through rates down close to 30% over the same period.
Visibility is no longer the same thing as traffic.
Pic. Click rate with vs without AI summary (Source).
The architect's job extends beyond the AI Max settings panel into the wider question of where the brand wants to appear, on whose terms, and against what economic standard. Each automation layer—Google's, Meta's, the major DSPs'—has its own black-box dynamics. The discipline that holds across all of them is the same: define the inputs deliberately, separate the campaign tiers, and measure outcomes against business objectives the platform cannot dictate.
The incremental impact standard
That last point is where the 2026 accountability conversation has settled. Writing for The Drum's year-ahead predictions, Joy Talbot of Analytic Partners argued that success in AI-led search will come from "understanding how AI-led search moments contribute to both brand and performance, not just last clicks." Reported ROAS inside an automated campaign now systematically overstates contribution. Holdout incrementality testing, marketing mix modeling and multi-touch attribution are the rebalancing instruments. Used together, they isolate the conversions the brand would not have earned without the spend, which is the only number that should set next quarter's budget.
The work has not got smaller. It has moved. The advertisers who win with AI Max in 2026 are not the ones who automate the most; they are the ones who design the boundaries the automation operates inside, then audit ruthlessly against incremental impact rather than platform-reported credit.
That is the discipline AI Digital exists to operationalize. Through our managed service, we run cross-channel buying with custom KPI optimization across CTV, Search, Display, Social and Native. Through Smart Supply, we curate the inventory layer that AI Max and Performance Max both depend on. Through Elevate, our intelligence platform, we give clients the marketing mix modeling, path-to-conversion analytics and cookieless reach that pull the measurement question back inside the brand's control. If your team is preparing for the September cutover and wants a partner that treats automation as something to be governed rather than deferred to, we should talk.
Blind spot
Key issues
Business impact
AI Digital solution
Lack of transparency in AI models
• Platforms own AI models and train on proprietary data • Brands have little visibility into decision-making • "Walled gardens" restrict data access
• Inefficient ad spend • Limited strategic control • Eroded consumer trust • Potential budget mismanagement
Open Garden framework providing: • Complete transparency • DSP-agnostic execution • Cross-platform data & insights
Optimizing ads vs. optimizing impact
• AI excels at short-term metrics but may struggle with brand building • Consumers can detect AI-generated content • Efficiency might come at cost of authenticity
• Short-term gains at expense of brand health • Potential loss of authentic connection • Reduced effectiveness in storytelling
Smart Supply offering: • Human oversight of AI recommendations • Custom KPI alignment beyond clicks • Brand-safe inventory verification
The illusion of personalization
• Segment optimization rebranded as personalization • First-party data infrastructure challenges • Personalization vs. surveillance concerns
• Potential mismatch between promise and reality • Privacy concerns affecting consumer trust • Cost barriers for smaller businesses
Elevate platform features: • Real-time AI + human intelligence • First-party data activation • Ethical personalization strategies
AI-Driven efficiency vs. decision-making
• AI shifting from tool to decision-maker • Black box optimization like Google Performance Max • Human oversight limitations
• Strategic control loss • Difficulty questioning AI outputs • Inability to measure granular impact • Potential brand damage from mistakes
Managed Service with: • Human strategists overseeing AI • Custom KPI optimization • Complete campaign transparency
Fig. 1. Summary of AI blind spots in advertising
Dimension
Walled garden advantage
Walled garden limitation
Strategic impact
Audience access
Massive, engaged user bases
Limited visibility beyond platform
Reach without understanding
Data control
Sophisticated targeting tools
Data remains siloed within platform
Fragmented customer view
Measurement
Detailed in-platform metrics
Inconsistent cross-platform standards
Difficult performance comparison
Intelligence
Platform-specific insights
Limited data portability
Restricted strategic learning
Optimization
Powerful automated tools
Black-box algorithms
Reduced marketer control
Fig. 2. Strategic trade-offs in walled garden advertising.
Core issue
Platform priority
Walled garden limitation
Real-world example
Attribution opacity
Claiming maximum credit for conversions
Limited visibility into true conversion paths
Meta and TikTok's conflicting attribution models after iOS privacy updates
Data restrictions
Maintaining proprietary data control
Inability to combine platform data with other sources
Amazon DSP's limitations on detailed performance data exports
Cross-channel blindspots
Keeping advertisers within ecosystem
Fragmented view of customer journey
YouTube/DV360 campaigns lacking integration with non-Google platforms
Black box algorithms
Optimizing for platform revenue
Reduced control over campaign execution
Self-serve platforms using opaque ML models with little advertiser input
Performance reporting
Presenting platform in best light
Discrepancies between platform-reported and independently measured results
Consistently higher performance metrics in platform reports vs. third-party measurement
Fig. 1. The Walled garden misalignment: Platform interests vs. advertiser needs.
Key dimension
Challenge
Strategic imperative
ROAS volatility
Softer returns across digital channels
Shift from soft KPIs to measurable revenue impact
Media planning
Static plans no longer effective
Develop agile, modular approaches adaptable to changing conditions
Brand/performance
Traditional division dissolving
Create full-funnel strategies balancing long-term equity with short-term conversion
Capability
Key features
Benefits
Performance data
Elevate forecasting tool
• Vertical-specific insights • Historical data from past economic turbulence • "Cascade planning" functionality • Real-time adaptation
• Provides agility to adjust campaign strategy based on performance • Shows which media channels work best to drive efficient and effective performance • Confident budget reallocation • Reduces reaction time to market shifts
• Dataset from 10,000+ campaigns • Cuts response time from weeks to minutes
• Reaches people most likely to buy • Avoids wasted impressions and budgets on poor-performing placements • Context-aligned messaging
• 25+ billion bid requests analyzed daily • 18% improvement in working media efficiency • 26% increase in engagement during recessions
Full-funnel accountability
• Links awareness campaigns to lower funnel outcomes • Tests if ads actually drive new business • Measures brand perception changes • "Ask Elevate" AI Chat Assistant
• Upper-funnel to outcome connection • Sentiment shift tracking • Personalized messaging • Helps balance immediate sales vs. long-term brand building
• Natural language data queries • True business impact measurement
Open Garden approach
• Cross-platform and channel planning • Not locked into specific platforms • Unified cross-platform reach • Shows exactly where money is spent
• Reduces complexity across channels • Performance-based ad placement • Rapid budget reallocation • Eliminates platform-specific commitments and provides platform-based optimization and agility
• Coverage across all inventory sources • Provides full visibility into spending • Avoids the inability to pivot across platform as you’re not in a singular platform
Fig. 1. How AI Digital helps during economic uncertainty.
Trend
What it means for marketers
Supply & demand lines are blurring
Platforms from Google (P-Max) to Microsoft are merging optimization and inventory in one opaque box. Expect more bundled “best available” media where the algorithm, not the trader, decides channel and publisher mix.
Walled gardens get taller
Microsoft’s O&O set now spans Bing, Xbox, Outlook, Edge and LinkedIn, which just launched revenue-sharing video programs to lure creators and ad dollars. (Business Insider)
Retail & commerce media shape strategy
Microsoft’s Curate lets retailers and data owners package first-party segments, an echo of Amazon’s and Walmart’s approaches. Agencies must master seller-defined audiences as well as buyer-side tactics.
AI oversight becomes critical
Closed AI bidding means fewer levers for traders. Independent verification, incrementality testing and commercial guardrails rise in importance.
Fig. 1. Platform trends and their implications.
Metric
Connected TV (CTV)
Linear TV
Video Completion Rate
94.5%
70%
Purchase Rate After Ad
23%
12%
Ad Attention Rate
57% (prefer CTV ads)
54.5%
Viewer Reach (U.S.)
85% of households
228 million viewers
Retail Media Trends 2025
Access Complete consumer behaviour analyses and competitor benchmarks.
Identify and categorize audience groups based on behaviors, preferences, and characteristics
Michaels Stores: Implemented a genAI platform that increased email personalization from 20% to 95%, leading to a 41% boost in SMS click through rates and a 25% increase in engagement.
Estée Lauder: Partnered with Google Cloud to leverage genAI technologies for real-time consumer feedback monitoring and analyzing consumer sentiment across various channels.
High
Medium
Automated ad campaigns
Automate ad creation, placement, and optimization across various platforms
Showmax: Partnered with AI firms toautomate ad creation and testing, reducing production time by 70% while streamlining their quality assurance process.
Headway: Employed AI tools for ad creation and optimization, boosting performance by 40% and reaching 3.3 billion impressions while incorporating AI-generated content in 20% of their paid campaigns.
High
High
Brand sentiment tracking
Monitor and analyze public opinion about a brand across multiple channels in real time
L’Oréal: Analyzed millions of online comments, images, and videos to identify potential product innovation opportunities, effectively tracking brand sentiment and consumer trends.
Kellogg Company: Used AI to scan trending recipes featuring cereal, leveraging this data to launch targeted social campaigns that capitalize on positive brand sentiment and culinary trends.
High
Low
Campaign strategy optimization
Analyze data to predict optimal campaign approaches, channels, and timing
DoorDash: Leveraged Google’s AI-powered Demand Gen tool, which boosted its conversion rate by 15 times and improved cost per action efficiency by 50% compared with previous campaigns.
Kitsch: Employed Meta’s Advantage+ shopping campaigns with AI-powered tools to optimize campaigns, identifying and delivering top-performing ads to high-value consumers.
High
High
Content strategy
Generate content ideas, predict performance, and optimize distribution strategies
JPMorgan Chase: Collaborated with Persado to develop LLMs for marketing copy, achieving up to 450% higher clickthrough rates compared with human-written ads in pilot tests.
Hotel Chocolat: Employed genAI for concept development and production of its Velvetiser TV ad, which earned the highest-ever System1 score for adomestic appliance commercial.
High
High
Personalization strategy development
Create tailored messaging and experiences for consumers at scale
Stitch Fix: Uses genAI to help stylists interpret customer feedback and provide product recommendations, effectively personalizing shopping experiences.
Instacart: Uses genAI to offer customers personalized recipes, mealplanning ideas, and shopping lists based on individual preferences and habits.
Medium
Medium
Share article
Url copied to clipboard
No items found.
Subscribe to our Newsletter
THANK YOU FOR YOUR SUBSCRIPTION
Oops! Something went wrong while submitting the form.
Questions? We have answers
Have other questions?
If you have more questions, contact us so we can help.