- Lead. Alphabet, Amazon, and Microsoft added a combined $1.5 trillion in market capitalisation in the week ending 31 July after all three reported cloud revenue growth that investors read as proof that their AI infrastructure spending is generating returns.
- Fact. Microsoft gained 19.4% for the week, Amazon 17.4%, and Alphabet 9.1%, helping drive the S&P 500 to a 2.8% weekly advance — its strongest since October 2023 — while Apple slid 4% after reporting below-consensus hardware numbers.
- Stake. The rally resets the AI capex debate that has weighed on mega-cap valuations since early 2026: markets now appear willing to reward companies whose cloud demand metrics justify the scale of their data-centre investment, while punishing those that cannot make the link explicit.
The three cloud hyperscalers reported second-quarter results in the final week of July and collectively shifted roughly $1.5 trillion in market value in a single week, according to CNBC. Microsoft ended the week up 19.4%, Amazon up 17.4%, and Alphabet up 9.1%, according to market data compiled by TradingKey. The S&P 500 rose 2.8% for the week, its best performance since October 2023.
The moves reversed a months-long pattern in which the market treated AI capital expenditure as evidence of cost inflation rather than demand. That anxiety had sent chip stocks lower ahead of the Federal Reserve’s July 29 meeting, as investors fretted that spending commitments were outrunning monetisable AI workloads.
Cloud Growth Answers the Capex Question
Each of the three companies reported cloud revenue figures that gave analysts a concrete connection between investment and demand. Microsoft’s Azure and other cloud services grew strongly, Amazon Web Services accelerated its revenue growth rate, and Alphabet’s Google Cloud posted comparable momentum. Across the board, management teams framed high capital expenditure as a response to customer backlog rather than speculative build-out.
The contrast with companies that could not make the same case was stark. Meta’s shares fell on the day of its results after investors questioned whether its AI spending was translating into near-term revenue, and Apple declined after hardware numbers underwhelmed. The divergence hardened a new market rule: AI capex that is tied to measurable demand growth is rewarded; AI capex that is not is punished.
Fed Provides Additional Lift
The rally was aided by the Federal Reserve’s 29 July decision to hold the federal funds rate in the 3.50%–3.75% range, accompanied by a statement noting “significant progress toward the two percent inflation objective” — language that market participants read as signalling rate cuts are drawing closer. Technology and communication services sectors led gains as Treasury yields fell, while defensive sectors lagged as investors rotated into growth.
The week ahead will test whether the momentum holds. Palantir reports results on Monday after the US close, with earnings from Spotify, AMD, Disney, and Eli Lilly all due later in the week. The July non-farm payrolls report, scheduled for Friday, carries particular weight: a reading that is too strong risks reviving “higher for longer” concerns that the previous week’s earnings had started to quiet. That had been the central worry gripping markets just ten days ago, before the earnings results came in.