Alphabet’s shares surged to a record high Thursday, after U.S. regulators stepped back from a proposed set of new restrictions on large AI platforms, a decision that unexpectedly strengthened the hand of Google’s parent company. But while regulatory relief is one factor, analysts say the real driver behind Google’s market-breaking rally lies in the success of its competitors. In fact, that’s what the judge in Google’s antitrust case said, too.

In a 230-page ruling, District Court Judge Amit Mehta wrote that Google can no longer enter into exclusive distribution deals around making its search engine or its Gemini AI technology into a default option, and that it must share some search data with competitors. But the decision stopped short of requiring it to spin off key assets, especially its Chrome web browser.

Mehta wrote that the emergence of generative AI has “changed the course of this case,” which began in 2020, several years before the mainstream release of ChatGPT fundamentally changed the tech sector. “The money flowing into this space, and how quickly it has arrived, is astonishing,” he wrote.

Alphabet’s stock closed up 8% Thursday at $231.10, its highest level ever.

Surprise on Wall Street