An S/MIME signature is not DKIM and not inbox placement.

Answer An S/MIME signature is not DKIM and not inbox placement. RFC 8551 is the S/MIME 4.0 message specification. The document is titled S/MIME Version 4.0 Message Specification. A signature on the content is not a domain signature. Do not cite an older S/MIME message spec as the current one. Current, here, means RFC 8551. Current still does not place the message, and it does not prove a stranger opted in. The signature rides with the content. The list is a separate fact.

Cream stationery and a teal accent on a dark navy desk — A content signature is not placement.

The note that started this: RFC 8551, S/MIME Version 4.0 Message Specification, RFC 8551.

Version numbers tempt a buyer who wants the send to sound modern. Modern is not a list. If you use solo ads for affiliate marketing, the offer still needs people who asked, on a domain you can name. An S/MIME signature does not supply either fact. It signs content. It is not DKIM, and it is not a domain signature. Do not merge those words because each of them can be called a signature on a careless call.

That is a fact about mail software. It is not a solo ad price, a rank, or proof that a stranger opted in. Inbox placement is a separate claim. The document does not make it. A signed letter can sit wherever the mailbox puts it. You do not get to point at S/MIME 4.0 and call the folder chosen. You also do not get to point at an older message spec and call it the current one.

Which document is the S/MIME message specification here?

RFC 8551 is the S/MIME 4.0 message specification. The document is titled S/MIME Version 4.0 Message Specification. Do not cite an older S/MIME message spec as the current one. A signature on the content is not a domain signature.

If a seller names an S/MIME message specification, ask whether they mean RFC 8551. If they mean an older one, they are not citing the current document. Do not treat every S/MIME paper as interchangeable. Even when the citation is current, the signature is on the content. It is not a domain signature, and it is not permission to mail the person who received it.

Sellers get the citation wrong when an old page is what they still read aloud. Update the citation or stop using the version as a sales point. Buyers should not pay extra for a version argument either way. S/MIME 4.0 on the content does not change the list. An older spec on the content does not change the list either. The list is the product.

The cited message spec is RFC 8551, or the version claim is dropped.
A content signature is not called DKIM.
Inbox placement is not claimed from the signature.
The list, the sending domain, and the refund line are on the order.

Is an S/MIME signature DKIM or inbox placement?

No. An S/MIME signature is not DKIM and not inbox placement. A signature on the content is not a domain signature. Inbox placement is a separate claim this document does not make. Do not cite an older S/MIME message spec as the current one, and do not cite the current one as placement either.

The buyer consequence is relief you did not earn. You hear signed and current, and you stop asking who received the letter. The signature did not answer. Ask for a received copy and read it as a letter. Ask which domain sent it. Placement is not a conclusion from RFC 8551, and a domain signature is not a conclusion from a signature on the content.

The seller consequence is a refund fight you framed in the pitch. If the order implied the signature was DKIM, or implied inbox placement, the buyer can point at the gap. Do not imply either one. Say you signed the content under the S/MIME 4.0 message specification if that is what you did. Then return to the list. The signature does not rent it.

Does S/MIME 4.0 prove a stranger opted in?

No. That is a fact about mail software. It is not a solo ad price, a rank, or proof that a stranger opted in. A buyer still has to name the list, the sending domain, and the refund line on the order.

A current signature on unwanted mail is still unwanted mail. The version tells you which message specification is being cited. It does not tell you that a person joined. Do not cite an older message spec to sound familiar, and do not cite RFC 8551 to sound finished. Finished is the order.

buy solo ads only after the list, the sending domain, and the refund line are on the paper. An S/MIME signature is not DKIM and not inbox placement. RFC 8551 will not fill those blanks. The letter is what you are renting. The signature is not a substitute for the person who asked.