The enthusiasm of investors following Apple's financial report has spilled over into Europe.

In early trading on Friday, the Dax was almost half a percent firmer at 17,964 points. A robust services business and the sales success of new laptop models helped the US technology giant to achieve sales above market expectations in the first quarter.

To underline its growing optimism, Apple announced the additional buyback of its own shares with a volume of 110 billion dollars. Jochen Stanzl, chief analyst at broker CMC Markets, urged caution: "The seven percent rise in the share price after the close should not obscure the fact that the iPhone business is still only doing moderately well. Apple will not be able to buy its way out of this problem every quarter with such a large share buyback."

Daimler Truck was also in the spotlight among companies. However, the truck manufacturer's shares were unable to maintain their pre-market gains after the publication of the figures for the first quarter. Pessimistic statements by CEO Martin Daum pushed the shares down by almost six percent. In contrast, Siemens Energy shares were in demand, rising by almost three percent. The experts at Deutsche Bank upgraded them to "buy" from "hold".

(Report by Zuzanna Szymanska, edited by Christian Götz. If you have any questions, please contact our editorial team at berlin.newsroom@thomsonreuters.com (for politics and the economy) or frankfurt.newsroom@thomsonreuters.com (for companies and markets).)