The majority of global prime office leasing deals were expansionary in H1 2026, including nearly four fifths of flex office deals and all major AI deals, according to data from Savills. More than half (56%) of these deals were for new office space within markets they already had an office presence, suggesting flex providers are deepening their footprint in their selected cities. Unsurprisingly, AI companies emerged as one of the fastest-growing occupier groups across the prime global office market. They accounted for 17% of all prime technology sector deals in H1, up from 3% two years ago, and every deal was expansionary. Leasing within the AI sector remains concentrated in established clusters, namely San Francisco and Seattle in the US and London’s West End.