Also known as “don’t use a company’s own public services to leak secrets about that company“.

In the day job we tell anyone wanting to put data onto a cloud service–no matter the service or the relationship with the vendor–to assume that data is compromised from the moment it’s online, if only by the company’s own employees. The real question is “do I trust Google/Microsoft/Apple/Amazon/whoever’s staff and contractors with my data”. If the answer is yes–and it often is–then the answer is yes and that’s fine. But you need to ask the question first, not just assume no one will or can look.