If there's no expired support contract, that would be making a false statement of fact in order to get someone to sign a contract and pay me money. It's plausible that that would be fraud.

Of course it's also plausible that that's not fraud at all. But I have no way to know for sure unless I ask a lawyer, which needless to say I wouldn't do. And if it turns out that it is fraud, well, the legal department of Fortune 500 companies tends to be pretty humorless.

Just say that "there is no active support contract for your company at this time."

Opensource license is a form of contract. I provide free 5 minute support to new users. And good luck suing me if I am not even US/EU based.

Departments (small managers) are authorized to spend small money without approval, lets say up to 200 euro/month. If they send this type of emails, someone ass is on fire. They will DO spend it just to get legal green light.

Anyway, I do not see reason to hold back, just because I am open source developer.

Why would you lie about a contract being expired when you could just say, "this software is provided without warranty (see license) - I offer support services starting at $X/day" and likely see the same result?

A already have enough work on $X/day. If they need to be compliant and treat me like their corporate drone, I am happy to comply. I can charge X*5 and spend one week working on my opensource project.

This is basic marketing. Airbnb, Facebook, Amazon etc are allowed to do shady stuff, but single contractor should be clean as lilium?

So... lie to someone who is making an effort to protect customer data in order to steal money?