By Josephine Mason
LONDON (Reuters) - Atos said on Tuesday it has alerted the French markets regulator after Berenberg withdrew its downgrade of the software company's stock, which briefly wiped almost 450 million euros ($503.42 million) off its market capitalization.
Analyst firm Berenberg on Tuesday issued a research note titled 'Unleash the bears', downgrading its rating on the stock to 'sell' and reducing its price target to 60 euro ($67) from 90 euro following Atos' sale of its stake in Worldline.
Berenberg later retracted the note, saying in an email that it had contained an error in its valuation approach and instead analyst Georgios Kertsos placed the stock under review.
"Analyst firm Berenberg issued this morning an analyst note on Atos, which was immediately withdrawn after realizing it contained a material error," Atos said on its website.
"This had a temporary impact on the stock price of Atos. The group has alerted the French Financial Markets Regulator (AMF)."
Berenberg, a private German bank based in Hamburg, declined to comment further and France's AMF declined to comment.
A change in recommendation on a company's stock can often influence the direction of its price. It's not known how the mistake at Berenberg occurred, but such a retraction is rare.
"In all the years I have been trading, this is the first time that I have seen a retraction," said one dealer.
Berenberg issued the retraction after being contacted by Atos' financial and investor relations team about an error in the report, an Atos spokesman said. He would not disclose any further details.
The downgrade knocked 444 million euros off the French company's market capitalization and sent its shares down almost 5 percent to 83.96 euros in early trading on Tuesday.
They recovered some ground after the retraction, but were still down 1.9 percent at 1514 GMT on the Paris bourse. The CAC 40 was up 0.2 percent.
With just under 775,000 shares traded, turnover in the stock was two-thirds higher than daily averages.
(Reporting by Josephine Mason, Thyagaraju Adinarayan and Helen Reid, additional reporting by Inti Landauro in PARIS; editing by Louise Heavens and Emelia Sithole-Matarise)