How anti-spam deposits protect your inbox
Unknown senders must post a refundable BMZ deposit before reaching you; it is returned when you engage. Tiered and cold-DM rate limits add more protection.
Quick answer: When someone who isn’t in your contacts tries to message you, Vaultr requires them to post a BMZ deposit before their message reaches you. The deposit is returned when you engage, so genuine senders get their stake back — while spammers face a real cost. Vaultr also applies tiered rate limits and cold-DM rate limiting to keep your inbox clean.
This turns the economics of spam upside down. Mass unsolicited messaging stops being free, so your inbox stays full of conversations you actually want.
How does the BMZ deposit work?
The deposit system targets messages from people you don’t know:
- An unknown sender — someone not in your contacts — wants to message you.
- Before their message reaches you, they must post a BMZ deposit.
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