Google and Amazon Vie for Big Inroad Into Wall Street Data Trove - Bloomberg

So cloud services are okay for, e.g., the CIA, but stock exchanges apparently have more stringent requirements

"Technology giants like Google parent Alphabet Inc. and Amazon.com Inc. are jumping at the chance to help build the storage for the exchanges via their cloud services. That’s intensified resistance by Wall Street, since the new database, known as the Consolidated Audit Trail, or CAT, could include personal information such as names and addresses from more than 100 million customer accounts. Brokers and banks are worried about everything from data breaches to technology firms making one of their biggest inroads yet into the financial world.
“This is a huge opportunity for Amazon and Google," said Jo Ann Barefoot, a senior fellow at Harvard University who studies fintech and a former official at the Office of the Comptroller of the Currency. “Their involvement in this project I do think is a threat to the incumbents. If big tech firms can win more trust in Washington, that’s one of the biggest challenges facing banks.”"

Google and Amazon Vie for Big Inroad Into Wall Street Data Trove - Bloomberg