TechTheft Watchlist Blacklist

The TechTheft Watchlist is an IP blocklist (blacklist). Use it for scoring, not blocking, to avoid collateral damage.

Updated on 17 Jun 2026: We updated this guide with safer DNSBL usage guidance, clearer delisting checks, and stronger IP reputation troubleshooting.

Summarize with

Check if you are listed on TechTheft Watchlist Blacklist

And 143 other blocklists.

Spamhaus

0Spam

Abusix

Barracuda Networks

Cisco

Mailspike

NoSolicitado

SURBL

UCEPROTECT

URIBL

8086 Consultancy

abuse.ro

ALPHANET

Anonmails

Ascams

BLOCKEDSERVERS

Brukalai.lt

Calivent Networks

dan.me.uk

DrMx

DroneBL

EFnet

Fabel

GBUdb

ImproWare

JIPPG Technologies

Junk Email Filter

JustSpam

Kempt.net

Mail Baby

NordSpam

nsZones

Polspam

RV-SOFT Technology

Schulte

Scientific Spam

Spam Eating Monkey

Spamikaze

SpamRATS

SPFBL

Suomispam

System 5 Hosting

Taughannock Networks

Team Cymru

Tornevall Networks

Validity

www.blocklist.de Fail2Ban-Reporting Service

ZapBL

2stepback.dk

Fayntic Services

ORB UK

RedHawk

technoirc.org

TechTheft

Spamhaus

0Spam

Abusix

Barracuda Networks

Cisco

Mailspike

NoSolicitado

SURBL

UCEPROTECT

URIBL

8086 Consultancy

abuse.ro

ALPHANET

Anonmails

Ascams

BLOCKEDSERVERS

Brukalai.lt

Calivent Networks

dan.me.uk

DrMx

DroneBL

EFnet

Fabel

GBUdb

ImproWare

JIPPG Technologies

Junk Email Filter

JustSpam

Kempt.net

Mail Baby

NordSpam

nsZones

Polspam

RV-SOFT Technology

Schulte

Scientific Spam

Spam Eating Monkey

Spamikaze

SpamRATS

SPFBL

Suomispam

System 5 Hosting

Taughannock Networks

Team Cymru

Tornevall Networks

Validity

www.blocklist.de Fail2Ban-Reporting Service

ZapBL

2stepback.dk

Fayntic Services

ORB UK

RedHawk

technoirc.org

TechTheft

Spamhaus

0Spam

Abusix

Barracuda Networks

Cisco

Mailspike

NoSolicitado

SURBL

UCEPROTECT

URIBL

8086 Consultancy

abuse.ro

ALPHANET

Anonmails

Ascams

BLOCKEDSERVERS

Brukalai.lt

Calivent Networks

dan.me.uk

DrMx

DroneBL

EFnet

Fabel

GBUdb

ImproWare

JIPPG Technologies

Junk Email Filter

JustSpam

Kempt.net

Mail Baby

NordSpam

nsZones

Polspam

RV-SOFT Technology

Schulte

Scientific Spam

Spam Eating Monkey

Spamikaze

SpamRATS

SPFBL

Suomispam

System 5 Hosting

Taughannock Networks

Team Cymru

Tornevall Networks

Validity

www.blocklist.de Fail2Ban-Reporting Service

ZapBL

2stepback.dk

Fayntic Services

ORB UK

RedHawk

technoirc.org

TechTheft

Spamhaus

0Spam

Abusix

Barracuda Networks

Cisco

Mailspike

NoSolicitado

SURBL

UCEPROTECT

URIBL

8086 Consultancy

abuse.ro

ALPHANET

Anonmails

Ascams

BLOCKEDSERVERS

Brukalai.lt

Calivent Networks

dan.me.uk

DrMx

DroneBL

EFnet

Fabel

GBUdb

ImproWare

JIPPG Technologies

Junk Email Filter

JustSpam

Kempt.net

Mail Baby

NordSpam

nsZones

Polspam

RV-SOFT Technology

Schulte

Scientific Spam

Spam Eating Monkey

Spamikaze

SpamRATS

SPFBL

Suomispam

System 5 Hosting

Taughannock Networks

Team Cymru

Tornevall Networks

Validity

www.blocklist.de Fail2Ban-Reporting Service

ZapBL

2stepback.dk

Fayntic Services

ORB UK

RedHawk

technoirc.org

TechTheft

Spamhaus

0Spam

Abusix

Barracuda Networks

Cisco

Mailspike

NoSolicitado

SURBL

UCEPROTECT

URIBL

8086 Consultancy

abuse.ro

ALPHANET

Anonmails

Ascams

BLOCKEDSERVERS

Brukalai.lt

Calivent Networks

dan.me.uk

DrMx

DroneBL

EFnet

Fabel

GBUdb

ImproWare

JIPPG Technologies

Junk Email Filter

JustSpam

Kempt.net

Mail Baby

NordSpam

nsZones

Polspam

RV-SOFT Technology

Schulte

Scientific Spam

Spam Eating Monkey

Spamikaze

SpamRATS

SPFBL

Suomispam

System 5 Hosting

Taughannock Networks

Team Cymru

Tornevall Networks

Validity

www.blocklist.de Fail2Ban-Reporting Service

ZapBL

2stepback.dk

Fayntic Services

ORB UK

RedHawk

technoirc.org

TechTheft

What is the TechTheft Watchlist blacklist?

The TechTheft Watchlist blacklist is a semi-manually curated DNS-based blacklist (DNSBL) that lists IP addresses. According to its operators, this blocklist is not intended for blocking email outright. It is designed for tagging, monitoring, and risk scoring, where being listed adds points to an email's overall spam score. The maintainers explicitly recommend against using it to block mail because that can cause collateral damage.

Listings are based on public nominations and abuse reports referencing a domain name, IP address, or netblock. This blacklist functions as a watchlist, meaning that listed entities are being monitored because of third-party claims of abuse, even without direct local evidence. For email troubleshooting, start with the outbound sending IP and then review the related hostname, rDNS, netblock ownership, and abuse history. TechTheft's watchlist covers a wide range of internet resources that come into contact with its spam and attack traps, including:

Email sources
DNS nameservers
Network IP blocks
Website hosts
Email servers
Virus-infected machines
Web crawling spiders and agents

Who runs the TechTheft Watchlist blacklist?

This blacklist is run by an organization named TechTheft. The group describes its mission as fighting high-technology theft, including viral attacks, spam, and DDoS attacks. It was formed as a collaborative point for administrators and hobbyists who wanted a stricter response to internet abuse than earlier anti-spam systems such as MAPS and SPEWS. TechTheft describes this strict approach as an "Internet Death Penalty" against sources and supporters of internet abuse.

How to get removed from the TechTheft Watchlist blacklist

Removal from the TechTheft Watchlist blacklist is done by request, but only after the underlying abuse issue has been resolved. Before requesting delisting from this blocklist, complete these checks:

Find and resolve every active abuse complaint associated with the listed IP address or netblock. A listing should not be treated as fixed until the behavior that caused it has stopped.
Keep a working abuse@ mailbox for the domain and IP space. Monitor it, answer complaints, and retain enough evidence to show what changed before asking for delisting.
Check the sending host for compromised accounts, open relays, web-form abuse, forwarded spam, malware, and unexpected outbound volume before assuming the blacklist entry is a false positive.

Once the complaints have been resolved, request removal and include the listed IP address, the abuse issue that was fixed, and the corrective action taken. The process is manual, and a specific public delisting form is not consistently available.

How to use TechTheft Watchlist safely

Use this DNSBL as a watchlist signal, not as a standalone rejection rule. A TechTheft Watchlist listing can support a wider IP reputation review, but hard blocking based on this blacklist alone creates false positives, especially for shared hosting, shared outbound mail platforms, and reassigned IP space.

Add only a small spam-score penalty for a match unless other evidence confirms abuse.
Review message headers, SMTP logs, complaint timestamps, and sending volume before treating the listing as the cause of delivery failures.
Avoid rejecting mail solely because of this blocklist or blacklist entry when the sending source is a shared provider or a recently reassigned IP address.
Use Suped's product to compare DMARC, SPF, DKIM, source alignment, and sending sources before treating the blacklist entry as the only cause.

Impact of a TechTheft Watchlist listing

The intended impact of being on this blacklist is low because the operators state that it should only be used for scoring or tagging emails, not blocking them. Individual system administrators still control their own mail server policy, so some receivers can reject mail based on this list. That misuse can create email delivery failures and collateral damage, especially when a listed IP address belongs to shared infrastructure.