SpamRATS RATS NoPtr Blacklist
SpamRATS NoPtr is an IP blocklist (or blacklist) identifying mail servers lacking valid reverse DNS or PTR records that send abusive traffic.
Updated on 17 Jun 2026: We updated this guide to clarify when RATS-NoPtr delisting applies and what to fix before requesting removal.
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Check if you are listed on SpamRATS RATS NoPtr Blacklist
And 143 other blocklists.
Spamhaus
0Spam
Cisco
NoSolicitado
URIBL
abuse.ro
ALPHANET
Anonmails
Ascams
BLOCKEDSERVERS
Calivent Networks
EFnet
JustSpam
Kempt.net
NordSpam
RV-SOFT Technology
Scientific Spam
Spamikaze
SpamRATS
SPFBL
Suomispam
System 5 Hosting
Team Cymru
Validity
www.blocklist.de Fail2Ban-Reporting Service
ZapBL
2stepback.dk
Fayntic Services
ORB UK
technoirc.org
TechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftWhat is the SpamRATS RATS-NoPtr blacklist?
The SpamRATS RATS-NoPtr blacklist is an IP-based blocklist for sending IP addresses that lack a valid reverse DNS or Pointer (PTR) record and have also shown abusive mail behavior. SpamRATS describes those signals as excessive connection attempts or attempts to deliver email to too many invalid users at ISP and telco mail servers. A missing PTR record is the defining trait of this RBL listing.
Any IP address running a mail server should have a PTR record that points to a hostname identifying the responsible operator, such as mail.yourdomain.com or mx.yourdomain.com. The hostname should also have sensible forward DNS back to the sending IP where possible. RATS-NoPtr focuses on networks that allow outbound port 25 traffic from IPs without reverse DNS, a pattern that fits compromised machines and improperly configured mail servers.
Who runs SpamRATS RATS-NoPtr?
SpamRATS runs the RATS-NoPtr blacklist. SpamRATS provides IP reputation lists, RBL services, and data feeds through mThreat Technology Inc. Its published lists include RATS-Dyna, RATS-NoPtr, RATS-Spam, and RATS-Auth, with RATS-NoPtr focused on reverse DNS problems tied to abusive SMTP traffic.
When should you request delisting?
Request removal only if you run or administer the affected mail server. If you are an end user sending through an ISP, mailbox provider, or company mail system, the fix usually sits with that provider or mail administrator, not with a direct SpamRATS removal request from you.
- If you manage the mail server, fix reverse DNS and confirm the IP no longer sends abusive port 25 traffic before requesting removal.
- If you do not manage the server, contact your ISP or help desk and ask for authenticated submission settings, commonly port 587 with SMTP authentication, instead of direct port 25 sending.
- If the lookup shows that RATS-NoPtr is not listed but another SpamRATS list is listed, follow the list-specific reason. A RATS-Dyna or RATS-Spam result is a different problem.
How to get removed from SpamRATS RATS-NoPtr
To get delisted from the SpamRATS RATS-NoPtr blacklist, resolve the underlying issue first. This blacklist targets sending IPs without a valid PTR record, so removal depends on correcting reverse DNS and stopping the abusive traffic that triggered the listing. If the IP belongs to a hosting provider or ISP, ask that provider to set the PTR record because reverse DNS is controlled by the owner or delegate of the IP allocation, not by your normal domain DNS zone.
- Create or update the PTR record for the sending IP so it points to a stable mail hostname, such as mail.yourdomain.com or mx.yourdomain.com.
- Confirm the hostname has matching forward DNS, the MTA banner and HELO/EHLO name are sensible, and the server is not sending to invalid addresses or creating excessive connection attempts.
- Allow DNS TTLs and provider processing to complete. Propagation often takes several hours, and the exact timing follows the old DNS TTLs plus the provider's reverse DNS update process.
- Use the official removal tool after the fix is visible. If automatic removal is not available, use the SpamRATS removal page or contact form for review.
What happens if your IP is listed?
The impact of being listed on the SpamRATS RATS-NoPtr blacklist depends on whether recipient systems query this RBL and how they apply the result. Mail from a listed IP can be rejected at SMTP time, filtered, or accepted with a negative reputation signal. For senders whose recipients use SpamRATS at the SMTP edge, the listing can create bounces and delivery delays.
Fixing PTR records also improves how receiving servers evaluate mail server identity, but it does not replace domain authentication and a DMARC policy. A clean DNS setup and authenticated mail flow reduce the chance that a blacklist (or blocklist) event becomes a recurring delivery problem.
Other SpamRATS blocklists
SpamRATS RATS Auth Blacklist
Organization
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Zone
auth.spamrats.com
Type
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Impact
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Delisting
Manual
SpamRATS RATS Dyna Blacklist
Organization
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Zone
dyna.spamrats.com
Type
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Impact
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Delisting
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SpamRATS RATS Spam Blacklist
Organization
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Zone
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Type
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Impact
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Delisting
Manual
