Amazon.com ( AMZN-Q) shares dropped nearly 8 per cent before the bell on Friday, after growth in its cloud computing unit failed to impress investors, in contrast to the robust gains reported by AI-focused rivals Alphabet ( GOOGL-Q) and Microsoft ( MSFT-Q ).

Amazon and Microsoft harming competition in cloud computing, finds CMA - It raised concerns over the way Microsoft charges Amazon and Google to use its software, which it said is driving up costs.

Though a small part of Amazon’s total revenue, AWS is a key driver of Amazon’s profits, typically accounting for about 60 per cent of the company’s overall operating income. AWS reported 16.9-per-cent growth in the first quarter.