Apple and Microsoft, the most valuable companies in the US, have argued that some of their flagship services are not popular enough to qualify as “gatekeepers” under groundbreaking new EU legislation designed to curb the power of Big Tech. FT: The battle between Brussels and Apple over its chat app iMessage and Microsoft’s Bing search engine is ahead of Wednesday’s publication of the first list of services subject to the digital markets law. The legislation places new responsibilities on technology companies, including sharing data, connecting with competitors and making their services interoperable with competing apps.