Scientific Spam Blocklist (BL)
The Scientific Spam blocklist (blacklist) targets IP addresses and domains sending unsolicited scientific spam to researchers and academics.
Updated on 17 Jun 2026: We updated this guide with current lookup steps and delisting scope for Scientific Spam Blocklist (BL).
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Check if you are listed on Scientific Spam Blocklist (BL)
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
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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.orgTechTheftThe Scientific Spam Blocklist (BL) is a niche DNSBL (DNS-based blocklist) and RHSBL (right-hand side blocklist) for unsolicited bulk email with a scientific or academic context. The spam it targets is sent to researchers, university staff, and authors whose addresses are often scraped from public sources such as PubMed, journal pages, conference programs, and research directories.
Conventional blacklists often have limited visibility into this category because the campaigns can be targeted and low-volume. Scientific Spam focuses on messages such as predatory journal solicitations, bogus academic conference invitations, research service pitches, and similar email sent to spam traps or participating researchers.
The operator's policy is to list spammers who send scientific spam to their spam traps and participating researchers. Listings are permanent until manually removed. The blocklist does not list senders for ordinary security issues such as hacked accounts, botnets, open relays, DNS problems, rDNS, SPF, DKIM, or DMARC failures, so fixing those items alone does not remove a listing.
Technical information
The blocklist operates two DNS zones:
- IP address based zone (bl.scientificspam.net): listed IP addresses return 127.0.0.2.
- Domain name based zone (rhsbl.scientificspam.net): listed domains return 127.0.1.2, which indicates that the domain is associated with scientific spam.
A TXT query for a listed IP or domain returns a human-readable reason. The usual format is a tag for a known spammer, the subject line, the sender address, and the listing date in yyyymmdd format. Subject lines can be adjusted to fit DNS record rules.
How to check a listing
Scientific Spam does not provide a web lookup form. Use direct DNS lookups so you query the active zones.
DNS lookup examplesbash
# For IPv4 address a.b.c.d, reverse the octets. dig +short d.c.b.a.bl.scientificspam.net A dig +short d.c.b.a.bl.scientificspam.net TXT # For a listed domain, append the RHSBL zone. dig +short example.com.rhsbl.scientificspam.net A dig +short example.com.rhsbl.scientificspam.net TXT
If the A query returns nothing, the queried resource is not listed in that zone. Check IP addresses in the IP zone and domains in the RHSBL zone; a domain TXT result does not prove the IP is listed, and an IP TXT result does not prove the domain is listed.
Who runs Scientific Spam Blocklist (BL)?
Scientific Spam Blocklist (BL) is managed by anonymous volunteers. The operators describe themselves as peers of the researchers whose contact information is public, including scientific authors whose addresses appear in databases and article metadata. They keep their identities private to reduce personal harassment directed at DNSBL operators.
The project has no formal organizational structure and is run as a public service. Its first purpose is protecting the operators' own email systems from scientific spam; the DNSBL data is published for mail server administrators who choose to use it. Third-party use is voluntary and each mail server administrator decides whether to query the list.
How do I get removed and delisted from Scientific Spam Blocklist (BL)?
Before requesting removal, confirm the listing with an A query and review the reason with a TXT query. The blocklist does not provide a web-based lookup tool. For IP address a.b.c.d, query d.c.b.a.bl.scientificspam.net. For a domain, query domain.example.rhsbl.scientificspam.net.
Once you have confirmed the listing and reviewed the TXT reason, request delisting by emailing rocket.scientists@scientificspam.net. Include enough detail to show that you checked the listing and understand why it exists.
- Write the email in plain text and preferably in English.
- Include the specific IP address or domain name, typed as text rather than only shown in a screenshot or image.
- Explain exactly what changed to stop the scientific spam. Authentication changes such as SPF, DKIM, or DMARC are not relevant unless the spam problem itself also stopped.
- If the TXT record points to a range, provider, or escalation listing, ask the sending provider or network owner to contact Scientific Spam directly.
- Do not justify the spam or claim it is legal under CAN-SPAM or another law.
- Use a mailbox that can receive their replies; a conversation is often required.
Removal requests should not be made through website comments or social media. The process is handled by email to keep removal requests private, consistent with DNSBL BCP guidance in RFC 6471.
What is the impact of being listed on Scientific Spam Blocklist (BL)?
For most senders, a Scientific Spam listing is not the same as being listed on a broad consumer-mailbox blocklist or blacklist. The list is specialized and its use is concentrated among universities, researchers, and independent mail server administrators who deal with academic spam.
That does not mean the list is inactive. The operator reported about 2 billion DNS queries against the IP zone in both 2023 and 2024, with the domain RHSBL receiving about half as many queries. A listing matters most when your recipients are academics, research groups, universities, labs, publishers, or scientific professionals.
The operator also noted in 2025 that more scientific spam is sent through Gmail and Microsoft 365. That reduces the usefulness of IP-only blocking, so domain-based signals and message content become more important for this niche.
