(Reuters) - Shares in Google parent Alphabet Inc (GOOGL.O) were up 4.9% on Thursday after it said it was rolling out its artificial-intelligence chatbot Bard in Europe and Brazil, easing worries about overseas regulatory issues.

The stock last traded at $124.73 and was on track for its biggest one-day percentage gain since early February when it announced the product. The shares also hit their highest point since mid-June during the session.

Alphabet shares were outperforming the broader market, with the S&P 500 (.SPX) up 0.6%, boosted by data showing signs of cooling inflation.

Bard's launch in the European Union had been held up until now by local privacy regulators but Google said it had met watchdogs to reassure them on issues relating to transparency, choice and control.

Danni Hewson, head of financial analysis at investment firm AJ Bell attributed Thursday's rally to the launch in Europe and in Brazil and Bard's expansion into new languages.

"There were some concerns about data, about privacy. Clearly they've been able to reassure European regulators about those issues, which just paves the way for further advantage really," said Hewson.

Art Hogan, chief market strategist at B Riley Wealth also attributed Thursday's rally to Bard's Europe and Brazil launch, which he said "marks the product's most significant expansion since its February launch and pits it against Microsoft Corp."

Microsoft, (MSFT.O) the backer of rival AI ChatGPT, was up 1.1% on Thursday.

Alphabet shares, which have seen a huge boost from investor excitement around generative artificial intelligence since February, are up around 41% so far this year. Microsoft shares are up 42% so far in 2023.

Also on Thursday, TD Cowen raised its price target for Alphabet shares to $140 from $130 citing expectations of better growth in its search business.