MJ12Bot is a bot in the SEO crawlers category, operated by Majestic.
MJ12bot is the web crawler for Majestic. MJ12Bot does not currently cache web content or personal data. Instead it maps the link relationships between websites to build a search engine. This data is available to technologies and the public, either by searching for a keyword or a website at Majestic.
SEO crawlers map links, keywords and technical issues for SEO tools and backlink databases. They help the tool's customers, often your competitors, rather than you. Rate limit or block the ones you do not use.
MJ12Bot identifies itself with this user agent string:
Mozilla/5.0 (compatible; MJ12bot/v1.4.8; http://mj12bot.com/)Anyone can copy a user agent string. Transfon Security also checks where each request comes from, so a request that claims to be a known crawler but comes from the wrong network is treated as a fake, not as the real crawler.
MJ12Bot follows robots.txt, so these rules stop it crawling the paths you choose. robots.txt is a plain text file at the root of your domain, such as https://example.com/robots.txt.
User-agent: MJ12bot Disallow: /
User-agent: MJ12bot Disallow: /private/ Disallow: /search
User-agent: MJ12bot Allow: /blog/ Disallow: /
User-agent: MJ12bot Allow: / User-agent: * Disallow: /
User-agent: MJ12bot group, MJ12Bot ignores your User-agent: * rules, so repeat any that should still apply.MJ12bot from MJ12Bot's user agent; check Majestic's own documentation if it publishes a different robots.txt name.Treat robots.txt as a statement of your policy, and enforce it where requests arrive.
MJ12Bot works for an SEO tool's customers, often your competitors. It adds server load without readers, so rate limit or block it unless you use the tool.
Transfon Security for publishersSEO crawlers map landing pages and links for competitor research. Keep MJ12Bot's visits out of campaign data.
Transfon Security for advertisersMJ12Bot can map your catalogue, prices and site structure for competitors. Block it unless you use the tool yourself.
Transfon Security for e-commerceAllow MJ12Bot only if your team uses the tool; otherwise rate limit it on docs and marketing pages.
Transfon Security for SaaS and APIsrobots.txt is a request, not an enforcement. Transfon Security shows MJ12Bot by name in the Top Bots report, so you can see how often it visits and which pages it reads. Block or allow it with a User Agent rule, or slow it down with a rate limit decision rule.
Transfon Security
MJ12Bot is a bot in the SEO crawlers category, operated by Majestic. MJ12bot is the web crawler for Majestic. MJ12Bot does not currently cache web content or personal data. Instead it maps the link relationships between websites to build a search engine. This data is available to technologies and the public, either by searching for a keyword or a website at Majestic.
Yes. MJ12Bot follows robots.txt, so a Disallow rule for the MJ12bot user agent stops it from crawling the paths you list.
Add "User-agent: MJ12bot" followed by "Disallow: /" to the robots.txt file at the root of your site. To enforce it, block requests whose user agent contains "MJ12bot" at your WAF. In Transfon Security that is one User Agent block rule.
No. robots.txt is voluntary, so MJ12Bot may not follow it, and anyone can send MJ12Bot's user agent, so a fake MJ12Bot ignores your rule. Enforce the rule where requests arrive, at your WAF, and check the source network.
SEO crawlers map links, keywords and technical issues for SEO tools and backlink databases. They help the tool's customers, often your competitors, rather than you. Rate limit or block the ones you do not use.
Transfon Security identifies every bot in this directory in your traffic reports, flags fake search crawlers, and lets you allow, block or rate limit each bot.
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