A new study from BrightEdge suggests AI search engines aren’t just answering questions—they’re quietly shaping brand reputations.

According to the company’s latest research, Google AI Overviews is 44% more likely to surface negative sentiment about brands than ChatGPT overall. But ChatGPT delivers criticism at a far more critical moment: right before customers make a purchase.

For chief marketing officers and digital teams, that dynamic introduces a new category of brand risk—one that traditional SEO metrics can’t fully capture.

The findings, powered by BrightEdge’s AI Catalyst platform, arrive as AI-powered search becomes mainstream. The company estimates more than three billion people now interact with Google AI Overviews and ChatGPT monthly, meaning AI-generated commentary about brands is reaching audiences at unprecedented scale.

And unlike traditional search results, where negative reviews might hide on page two, AI systems often summarize sentiment directly in the answer.

AI Is Becoming a Brand’s Editorial Voice

In many ways, AI search behaves like an editor.

Rather than simply indexing content, modern AI systems analyze information across the web—including news coverage, reviews, forum discussions, and historical controversies—and compress it into a single response.

That means a brand’s digital past, including long-forgotten controversies or outdated reviews, can resurface instantly when users ask questions.

“For better or worse, AI is your brand’s new editorialist,” said Jim Yu. “Each engine characterizes your brand differently, and CMOs must treat them as distinct, dynamic environments.”

Negative Sentiment Is Rare—but Still Massive

At first glance, the amount of negative sentiment appearing in AI responses seems relatively small.

BrightEdge found that:

• Google AI Overviews show negative sentiment in about 2.3% of brand mentions

• ChatGPT shows negative sentiment in about 1.6% of mentions

But scale changes the equation.

Across billions of queries each month, even those small percentages translate into millions of negative brand exposures delivered directly in AI-generated answers.

And because AI responses are often reused across similar queries, the same criticism may appear repeatedly for many users asking similar questions.

Google vs. ChatGPT: Two Very Different Critics

The study also found that the two AI systems behave differently when evaluating brands.

Google AI Overviews tends to surface negativity tied to controversy and external events, including:

• Lawsuits

• Regulatory scrutiny

• Product recalls

• Data breaches

• Public boycotts

In contrast, ChatGPT focuses more on product-level critiques, including:

• Feature limitations

• Compatibility issues

• Value-for-money debates

• Purchase recommendations

The result is that the same brand might face very different criticism depending on the AI platform.

A retailer might appear in Google’s AI responses because of a lawsuit mentioned in the news, while ChatGPT might highlight product return policies or payment restrictions.

The divergence stems largely from their source ecosystems.

Google’s AI Overviews lean heavily on news coverage and authoritative media, while ChatGPT often reflects product reviews, community discussions, and forums like Reddit.**

ChatGPT Hits Hardest Near the Point of Purchase

Perhaps the most surprising finding is when negative sentiment appears.

Most criticism in Google AI Overviews appears early in the customer journey.

BrightEdge found that 85% of Google’s negative sentiment surfaces during informational searches, when users are researching products or building shortlists.

ChatGPT behaves very differently.

While 68.5% of its negative responses also occur during the informational stage, nearly 19.4% appear during the consideration-to-purchase phase—when consumers are deciding whether to buy.

That’s 13 times higher than Google’s 1.5% rate at that stage.

In other words:

• Google shapes brand perception early in the funnel

• ChatGPT can directly influence conversion decisions

For marketers, that difference matters.

A negative AI response at the research stage may influence awareness. But criticism delivered just before purchase can derail a sale entirely.

AI Engines Rarely Agree on Which Brand Is at Fault

Another surprising discovery: AI platforms often disagree about which brand deserves criticism.

When BrightEdge analyzed queries where both engines surfaced negative sentiment, Google and ChatGPT flagged different brands 73% of the time.

This suggests that monitoring a single AI platform provides an incomplete view of brand perception.

Instead, companies may need to track sentiment across multiple AI ecosystems—each with its own content sources, ranking signals, and reasoning models.

Industry Differences Are Emerging

The research also found that AI criticism varies significantly by industry.

For example:

Electronics:
Both platforms show higher negativity rates, with Google leading due to product recalls and technology controversies.

Education:
Google is nearly twice as negative as ChatGPT, reflecting coverage tied to political and institutional scrutiny.

Apparel:
The pattern flips. ChatGPT is three times more negative than Google, largely because product evaluations dominate the conversation rather than controversy.

For brands, that means AI sentiment monitoring must be tailored to the dynamics of each vertical.

AI Is Surfacing the Internet’s Long Memory

Another challenge highlighted in the report is the way AI engines resurface historical content.

Because AI summarizes information across a brand’s entire digital footprint, events from years—or even decades—ago can reappear in modern responses.

Examples cited by BrightEdge include:

• A decade-old smartphone safety recall appearing in responses to queries about battery life

• A celebrity-brand partnership discussed in an old Reddit thread resurfacing as evidence of brand sentiment

• Insurance companies criticized for not renewing homeowner policies in California appearing in AI comparisons

In traditional search, users might need to dig through multiple pages to find such content.

In AI-driven search, those details appear instantly in the answer.

A New Metric for CMOs: AI Sentiment Visibility

For marketing leaders, the takeaway is clear: AI search has introduced a new layer of brand management.

Tracking visibility in AI-generated answers is no longer enough.

Companies now need to monitor how AI describes their brand, not just whether it appears in results.

That includes measuring:

• AI sentiment across platforms

• Share of voice in AI responses

• Source ecosystems influencing AI answers

• Funnel-stage impact on conversions

“Sentiment monitoring across all AI engines is no longer optional,” Yu said. “It’s a revenue imperative.”

As generative AI continues to reshape search, brands may find themselves optimizing not just for algorithms—but for AI’s evolving editorial judgment.

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