ChatGPT uses Google search despite official Bing partnership claims

Two independent research studies released in July and August 2025 have provided conclusive evidence that ChatGPT's paid version uses Google Search results rather than its officially documented Bing partnership. The findings challenge OpenAI's public documentation and raise questions about data transparency in artificial intelligence search systems.

Abhishek Iyer, a former Google search infrastructure engineer who now operates ACME.BOT, announced his findings on July 19, 2025. His research employed what he termed a "sting operation" similar to Google's 2011 investigation into Bing's search practices. The methodology involved creating a unique, non-existent term and tracking its appearance across different search engines and AI platforms.

Backlinko's Brian Dean conducted a parallel investigation that confirmed Iyer's discoveries. Publishing results on August 6, 2025, the study used the fabricated term "NexorbalOptimization" to test whether ChatGPT accessed Google's exclusive search index.

The research methodology centered on creating terms with zero online presence. Iyer used "myshkalapatnaik" while Dean selected "NexorbalOptimization." Both researchers created dedicated web pages containing these terms, then configured server access to allow only Google's crawling bot while blocking all other search engines and AI platforms through robots.txt modifications.

"We made up a new SEO buzzword: NexorbalOptimization. It had zero mentions online, no search volume, no overlap with real words, acronyms, or brand names," Dean explained in his documentation. The Backlinko team implemented specific crawling restrictions: "Googlebot could crawl and index the page. Bing, Perplexity, DuckDuckGo, Claude, and other bots were blocked."

After Google indexed both test pages, the researchers queried multiple AI platforms about their fabricated terms. ChatGPT Plus consistently returned detailed information about both terms, quoting directly from the restricted pages that only Google had accessed. "Now suddenly ChatGPT starts quoting from this dummy hidden webpage that only Google knows about," Iyer documented.

The results revealed stark differences between ChatGPT versions. While ChatGPT Plus accurately described both fabricated terms using content from the Google-indexed pages, ChatGPT's free version returned no information about either term. "When checked with the free version of ChatGPT, our dummy term does not show up at all – suggesting that the free version of ChatGPT likely uses some other search engine," Iyer reported.

Testing across other AI platforms produced varied results. Claude 4 Sonnet found neither term. Perplexity successfully located Dean's "NexorbalOptimization" page but failed to find Iyer's term. This pattern suggests different AI platforms utilize distinct search infrastructure partnerships.

Iyer conducted additional analysis comparing ChatGPT's search results with those from Google and Bing directly. He measured domain overlap and snippet similarity across multiple queries, finding that ChatGPT's results aligned closely with Google while showing significant divergence from Bing.

"We found that the results from ChatGPT are most similar to Google's search results. On the other hand, they are actually quite dissimilar to Bing's search results," Iyer documented. His analysis included metrics showing search result domain overlap reaching 1.0 with Google, indicating complete alignment, while showing lower correlation with Bing results.

The findings contradict OpenAI's official documentation, which states that ChatGPT search results may be sent to Bing or Shopify but makes no mention of Google integration. According to help documentation at https://help.openai.com/en/articles/9237897-chatgpt-search, "results may be sent to Bing or Shopify, but not Google."

OpenAI officially announced ChatGPT Search on October 31, 2024, during a Reddit Ask Me Anything session. Chief Product Officer Kevin Weil stated that the search functionality "leverages multiple services, with Bing playing an important role in the implementation." However, the recent research suggests this characterization may not accurately represent the underlying technical architecture.

The discovery carries significant implications for search engine optimization strategies. "This means the whole SEO / Answer Engine Optimization (AEO) narrative has come full circle from 'Google is dead' -> 'rank in Google to show up on ChatGPT'!" Iyer noted in his analysis.

Marketing professionals have tracked increasing referral traffic from AI platforms. Similarweb data published July 2, 2025 showed ChatGPT referrals to news publishers increased 25 times year-over-year, while zero-click searches on Google grew from 56% to nearly 69% since AI Overviews launched in May 2024.

The research also reveals technical implementation details. Iyer found URLs containing Google's unique "srsltid" parameter in ChatGPT responses, suggesting direct integration with Google's search infrastructure rather than indirect data access.

For content creators and publishers, the findings indicate that Google indexing remains crucial for AI search visibility. "If Google doesn't index you — many AI tools won't surface you," Dean concluded in his analysis. This reality contradicts predictions that AI search would diminish Google's influence in content discovery.

The investigation methods mirror Google's 2011 "Bing Sting" operation, when Google accused Microsoft of copying its search results. That investigation used the fabricated search term "hiybbprqag" to demonstrate result copying. Iyer noted the historical parallel: "Ironically, back in 2011 Google had accused Bing of stealing Google's search results. Looks like the same test is quite relevant even today!"

Privacy implications emerge from the undisclosed Google integration. Users of paid ChatGPT services may unknowingly have their search data transmitted to Google without explicit consent. "However, as a paying ChatGPT user, now your data is being sent to Google without your consent," Iyer observed.

The competitive landscape has shifted dramatically since ChatGPT's November 2022 launch. Industry analysis suggests ChatGPT could potentially overtake Google search traffic by 2030, driven by superior conversion rates and user engagement metrics.

Microsoft maintains its advertising partnership with OpenAI while operating its own search infrastructure. Microsoft's advertising business reached $20 billion annually as of May 1, 2025, with growth attributed partly to AI-powered search features in Bing and Edge.

However, Microsoft has simultaneously reduced its search API availability. The company announced on June 9, 2025, that Bing Search APIs would be retired on August 11, 2025, with replacement services costing 40-483% more and requiring Azure integration.

The research suggests OpenAI may operate its own search infrastructure for the free ChatGPT version. "OpenAI was rumored to have been working on their own search engine and it is likely that they are using / testing this out on the free version of ChatGPT," Iyer speculated.

Search engine market dynamics continue evolving as AI platforms establish new partnerships. OpenAI announced a data licensing partnership with Reddit on May 17, 2024, providing access to real-time, structured content for language model training.

For marketing professionals, the findings necessitate strategic adjustments. Recent data shows 68% of marketers currently focus on ChatGPT/OpenAI platforms for tracking search presence, while only 17% actively track visibility within Google's AI Overviews despite Google's market dominance.

Analytics platforms have responded to increasing AI traffic. Google Analytics now provides specific guidance for measuring traffic from ChatGPT, Gemini, and other AI tools through custom channel group configurations implemented just two days ago.

The undisclosed Google integration raises questions about transparency in AI partnerships. While OpenAI maintains an official Microsoft partnership for search capabilities, the technical implementation appears to rely primarily on Google's search infrastructure for paid users.

Both research studies employed rigorous methodologies to ensure accuracy. The sting page approach provides definitive proof because it eliminates alternative explanations for how ChatGPT could access the restricted content. Only Google's search index contained the fabricated terms, making it impossible for ChatGPT to have obtained the information through other channels.

The findings align with broader trends in AI search development. Major platforms are launching specialized tracking tools, with Similarweb unveiling its GenAI Intelligence Toolkit on July 28, 2025, to monitor brand visibility across AI chatbots including ChatGPT, Perplexity, Gemini, Grok, and CoPilot.

Industry response to the research has focused on implications for search optimization strategies. The discoveries suggest that traditional SEO fundamentals remain relevant for AI search visibility, including crawlability, fast indexing, and content structured for semantic clarity.

The research validates growing marketer attention to AI search optimization. Despite representing only 0.5% of total website visits, AI search traffic generates 12.1% of all signups, indicating users arriving from AI platforms demonstrate higher conversion intent than traditional search traffic.

Technical implementation details revealed by the research suggest ChatGPT processes Google search results through its language models rather than simply displaying raw search results. This approach allows for natural language responses while maintaining access to Google's comprehensive web index.

The investigation timeline began with Iyer's initial sting operation in July 2025, followed by Dean's confirmation study in August. Both researchers published their findings independently, with similar conclusions despite using different fabricated terms and slightly varied methodologies.

Timeline

• November 2022: ChatGPT launches, bringing generative AI into mainstream use
• February 2023: Microsoft debuts Copilot, first large language model deeply integrated with search
• May 17, 2024: OpenAI and Reddit forge partnership for data licensing and AI-powered features
• July 27, 2024: OpenAI launches SearchGPT prototype challenging Google directly
• October 31, 2024: ChatGPT launches Web Search with news partners for real-time updates
• November 1, 2024: OpenAI partners with Bing to power new ChatGPT Search
• May 1, 2025: Microsoft ad revenue tops $20 billion as Copilot transforms search
• June 9, 2025: Microsoft ends Bing Search APIs on August 11, alternative costs 40-483% more
• June 18, 2025: ChatGPT could overtake Google search traffic by 2030
• July 2, 2025: ChatGPT referrals surge as Google searches hit zero-click records
• July 19, 2025: Abhishek Iyer publishes initial research proving ChatGPT uses Google Search
• July 28, 2025: Similarweb launches dual tracking platform for AI search optimization
• August 5, 2025: Google Analytics now suggests tracking AI chatbots in custom channel groups
• August 6, 2025: Backlinko publishes confirmation study using "NexorbalOptimization" term

Key Terms Explained

Google: The search engine giant that emerged as the unexpected backbone of ChatGPT's paid search functionality, despite no official partnership announcement. Research revealed that ChatGPT Plus consistently accesses Google's search index rather than Microsoft's Bing, creating significant implications for search engine optimization strategies. This discovery means that content visibility in Google directly influences AI-generated responses, reinforcing rather than diminishing Google's central role in information discovery across digital platforms.

ChatGPT: OpenAI's conversational artificial intelligence platform that launched in November 2022 and has become the most widely recognized AI assistant globally. The platform operates with distinct search mechanisms between its free and paid versions, with the premium ChatGPT Plus secretly utilizing Google's search infrastructure while the free version appears to operate on OpenAI's proprietary search system, creating different user experiences and access to information sources.

Search: The fundamental process of information retrieval that has been transformed by artificial intelligence integration, shifting from traditional keyword-based queries to conversational interfaces that provide synthesized answers. Modern search encompasses both traditional web search through engines like Google and Bing, as well as AI-powered search that generates responses by processing and combining information from multiple sources in real-time conversations.

OpenAI: The artificial intelligence research company founded in 2015 that created ChatGPT and has become a central player in the AI search landscape. The company's undisclosed use of Google's search infrastructure in its paid services raises questions about transparency in AI partnerships and data handling practices, particularly regarding user privacy and the routing of search queries through undocumented third-party systems.

Research: The systematic investigation methodology employed by multiple independent teams to uncover the true search partnerships behind AI platforms. Both Abhishek Iyer and Backlinko conducted rigorous "sting operations" using fabricated terms indexed exclusively by Google, providing definitive evidence that contradicted OpenAI's official documentation about its search infrastructure and partnerships.

Bing: Microsoft's search engine that officially partners with OpenAI to provide search capabilities for ChatGPT, according to public documentation and company announcements. However, empirical research suggests this partnership may be largely ceremonial or limited to specific functions, with the actual search results in ChatGPT Plus coming primarily from Google's index rather than Bing's search infrastructure.

AI: Artificial intelligence technology that has fundamentally altered how users interact with information systems, moving from simple search result lists to conversational interfaces that understand context and generate human-like responses. AI search platforms like ChatGPT, Perplexity, and Google's AI Overviews represent a paradigm shift in information retrieval, though they still rely heavily on traditional search engine indexes for their underlying data.

Results: The information outputs generated by search engines and AI platforms in response to user queries, which can range from traditional ranked web page lists to synthesized conversational responses. The research revealed significant differences in result quality and sources between ChatGPT's free and paid versions, with paid users receiving information derived from Google's comprehensive index while free users access a more limited dataset.

Content: The digital information including web pages, articles, and multimedia that search engines index and AI systems synthesize into responses. Content creators and marketers must now optimize for both traditional search visibility and AI consumption, ensuring their material can be properly indexed by Google to maximize chances of appearing in AI-generated answers across platforms like ChatGPT.

Platform: The digital infrastructure and user interfaces through which people access AI-powered search capabilities, including ChatGPT, Google's AI Overviews, Perplexity, and Microsoft Copilot. Each platform operates with distinct search partnerships and data sources, creating a fragmented landscape where visibility strategies must account for multiple AI systems with different underlying technologies and content access mechanisms.

Summary

Who: Abhishek Iyer, former Google search infrastructure engineer and ACME.BOT operator; Brian Dean and the Backlinko research team; OpenAI and ChatGPT users; marketing professionals tracking AI search visibility

What: Two independent research studies proved that paid ChatGPT versions use Google Search results despite official documentation claiming Bing partnership; free ChatGPT version operates on separate search infrastructure; findings contradict OpenAI's public documentation about search partnerships

When: Initial research published July 19, 2025, with confirmation study released August 6, 2025; ChatGPT Search officially launched October 31, 2024, with Bing partnership announcement November 1, 2024

Where: Global impact affecting AI search platforms, digital marketing strategies, and search engine optimization practices; technical investigation used fabricated terms indexed exclusively by Google's search infrastructure

Why: Research aimed to understand actual search partnerships behind AI platforms amid growing importance of AI search optimization for marketing professionals; findings reveal significant transparency issues and implications for SEO strategies as AI search traffic demonstrates superior conversion rates despite representing small percentage of total website visits