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Suppose I have a domain ( with an SPF that looks like this:

v=spf1 ip4: -all

and "" looks like this

v=spf1 ip4: ~all

What takes precedence for, the "~" or the "-"? Does the tilde in the marketing company's SPF negate all SPF benefit for

Is this behavior consistent among all SPF parsers?

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up vote 5 down vote accepted

Assuming that all parsers adhere to the RFC4408 specification, the -all from the record applies. The include does not modify the verification process, it merely expands it to include the mechanisms contained in the included record.

If you were to use redirect in place of include, like this for

v=spf1 ip4: -all

the ~all would apply, and -all would be discarded in the verification sequence. That is, again, assuming that all parsers adhere to the specification

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