Some companies should never get an email from you: current customers, partners, competitors, or a company that asked you to stop. You can now add their domain to a Blocked Domains list, and FirstSales will skip every address at that domain.
What changed
Blocked Domains work at two levels. A workspace block covers every campaign. A campaign block covers only that one campaign, which is handy when a company is fine to contact for one offer but not another.
Before any email goes out, FirstSales checks the recipient's domain against both lists. A match means the email is not sent. You can also ask whether an address would be blocked before you add it to a campaign.
How to use it
Blocked Domains are available through the API, the CLI and the Claude connector. Add a domain, list what is blocked, or check one address.
Why it matters
One wrong email to a current customer can cost more than a hundred good cold emails earn. Blocking by domain stops that mistake for every person at the company, including people you have not imported yet.