OpenAI's Golden Touch: How An AI Giant Now Moves Markets and Fuels Bubble Fears

OpenAI's "Golden Touch": The AI Halo Effect and Market Volatility

An offhand remark from OpenAI, the world's most valuable private startup as of October 2025, now has the ability to markedly revalue public companies, producing a distinct "AI halo effect" across global financial markets. This phenomenon, clearly evident during OpenAI's DevDay conference on Monday, October 6, 2025, has generated significant, frequently immediate, gains for partner firms, while analysts warn of a possible "AI bubble."

During DevDay, OpenAI CEO Sam Altman announced collaborations with several companies, including Figma, HubSpot, Salesforce, and Expedia. Each partnership announcement from the stage sparked a measurable rise in the respective firms' stock prices, ranging from 2% to 7% intraday. Notably, shares of design-software provider Figma jumped over 7%, whereas Expedia added roughly 2%. Even toy maker Mattel experienced a 6% intraday surge after a demonstration that highlighted the company's use of OpenAI's Sora video generator. Likewise, Uber and DoorDash, slated to join the App SDK lineup, each saw near-4% gains, propelling them into the top performers of the S&P 500 on that day.

The most dramatic illustration of this market reaction involved Advanced Micro Devices (AMD). Following the disclosure of an agreement between OpenAI and the chipmaker- which included a potential equity stake for OpenAI of up to 10% of AMD, contingent on stock price and partnership milestones-AMD shares vaulted 24% on Monday, October 6th. That single-day jump translated into a $63 billion increase to AMD's market capitalization. By Wednesday, October 8th, AMD's stock had risen an additional 11%, lifting its weekly gain to an impressive 43%, its best weekly performance since April 2016, and expanding its market cap to $380 billion. This partnership has notably bolstered investor confidence in AMD's ability to challenge Nvidia's dominance in the AI-chip arena.

Joe Saluzzi, a partner at Themis Trading, described the current climate as a "momentum market, where anything related to OpenAI moves stocks and people throw fundamentals out the window." This view underscores a broader trend in which enthusiasm for AI-linked ventures appears to outweigh traditional valuation metrics.

However, the durability of this "golden touch" remains a point of ongoing debate among financial experts. The Financial Times reported that the rapid investor interest is predicated on continued growth in AI usage, suggesting that any slowdown could swiftly erode this excitement. Amazon founder Jeff Bezos has also publicly voiced concerns about the emergence of an "AI bubble," echoing a sentiment shared by other industry observers.

Conversely, some analysts see these partnerships as essential for the maturation of AI technology. Anurag Rana, a Bloomberg Intelligence analyst, argued that such collaborations help software firms pinpoint concrete AI use cases and attract new users. This perspective holds that the current surge, while speculative, also serves to embed AI more deeply across diverse sectors, potentially allaying fears of widespread disruption by demonstrating practical applications.

These dynamics highlight OpenAI's significant, albeit indirect, influence on public markets, establishing it as a "kingmaker" capable of shaping investor perceptions and driving substantial capital flows based on perceived association with cutting-edge AI innovation. The question remains whether this market behavior reflects genuine technological progress or the early stages of a speculative frenzy.