Peer39Crawler is a bot in the advertising and marketing bots category, operated by Peer39.
Peer39Crawler reads pages for Peer39, which classifies them into contextual and brand safety categories that advertisers use to target and filter ads.
Advertising bots review landing pages, check ad placements and classify pages for brand safety and contextual targeting. Blocking ad verification bots can stop your ads or your inventory from serving, so allow the ones your ad partners use.
Peer39Crawler identifies itself with this user agent string:
peer39_crawler/1.0Anyone 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.
We have not confirmed whether Peer39Crawler follows robots.txt. Add a rule, then check your logs to see that it stopped. robots.txt is a plain text file at the root of your domain, such as https://example.com/robots.txt.
User-agent: peer39_crawler Disallow: /
User-agent: peer39_crawler Disallow: /private/ Disallow: /search
User-agent: peer39_crawler Allow: /blog/ Disallow: /
User-agent: peer39_crawler Allow: / User-agent: * Disallow: /
User-agent: peer39_crawler group, Peer39Crawler ignores your User-agent: * rules, so repeat any that should still apply.peer39_crawler from Peer39Crawler's user agent; check Peer39'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.
Ad verification and contextual crawlers like Peer39Crawler can decide whether your pages get demand. Blocking the ones your partners use can lower fill rates.
Transfon Security for publishersPeer39Crawler checks pages for ad platforms. Its visits to landing pages are not users, so exclude them from conversion data.
Transfon Security for advertisersAd platforms send crawlers like Peer39Crawler to check product landing pages. Keep it allowed so ads are not disapproved, and out of analytics.
Transfon Security for e-commerceAllow Peer39Crawler on landing pages linked from your ads, and keep it off the app.
Transfon Security for SaaS and APIsrobots.txt is a request, not an enforcement. Transfon Security shows Peer39Crawler 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
Peer39Crawler is a bot in the advertising and marketing bots category, operated by Peer39. Peer39Crawler reads pages for Peer39, which classifies them into contextual and brand safety categories that advertisers use to target and filter ads.
We have not confirmed whether Peer39Crawler follows robots.txt. Add a robots.txt rule, then check your logs to see that it stopped, and block it by user agent if it did not.
Add "User-agent: peer39_crawler" followed by "Disallow: /" to the robots.txt file at the root of your site. To enforce it, block requests whose user agent contains "peer39_crawler" at your WAF. In Transfon Security that is one User Agent block rule.
No. robots.txt is voluntary, so Peer39Crawler may not follow it, and anyone can send Peer39Crawler's user agent, so a fake Peer39Crawler ignores your rule. Enforce the rule where requests arrive, at your WAF, and check the source network.
Advertising bots review landing pages, check ad placements and classify pages for brand safety and contextual targeting. Blocking ad verification bots can stop your ads or your inventory from serving, so allow the ones your ad partners 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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