In reviewing the headers on some spam I received I'm finding origination IP addresses in IANA reserved blocks. Aren't these addresses supposed to be blocked from use? Are they spoofed? If so, is there anyway to find the real sending address?

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ex:

Received: from dochristsangareepf61 (incongruity[106.204.168.130])
by worldnet.att.net (nhjlbhs05) with SMTP
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