Google received and responded to legal process issued by FBI compelling the release of information related to your Google account. A court order previously prohibited Google from notifying you of the legal process. We are now permitted to disclose the receipt of the legal process to you.
What does that mean ?
It just means the FBI is allowed to continue their investigations but Google is no longer prohibited from telling you about it. In court terms it means the gag order has been lifted.
What it means(to me), unless you have done something illegal, or are associated with someone who has, and there is a reason Johnny Law is looking at your information, you're Gmail account might have either been hacked, or pwned, and you need to immediately change your password and setup & start using two part authentication(if you have a cell phone and can).
Go here to see if your Email address('s) has/have possibly been pwned: Have I been pwned? Check if your email has been compromised in a data breach
It's run by Troy Hunt, a Microsoft Regional Director and Most Valuable Professional(see the "Who what, & why page)
I saw this :
Good news — no pwnage found!
No breached accountsand no pastes (subscribe to search sensitive breaches)
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