This is per the BusinessInsider
Ceridian
Why it could be a target: Having a suite of human resources management applications in the cloud has become increasingly important. Trevor White, an analyst with Nucleus Research, says that this is "one area in the tech stack where Microsoft really doesn't compete." He thinks Ceridian would be a logical target.
"It is not out of the realm of Microsoft spending," he told Business Insider. The company spent over $9 billion on acquisitions last year.