410 Gone
The honest sibling of 404: it existed, it was removed for good — stop looking.
404 says "not found", committing to nothing. 410 signs its name: it existed, it was removed on purpose, it is not coming back. RFC 9110 recommends it exactly for that honesty — ended promotions, deleted accounts, retired content.
The distinction has practical consequence: search engines drop a page answering 410 from the index faster, and podcast aggregators use it as the formal request to unsubscribe from a dead feed. It is protocol politeness: saying there is no point in coming back.
HTTP/1.1 410 Gone
Content-Type: text/html
Cache-Control: max-age=31536000
<h1>Este endereço foi aposentado.</h1>