Transfon Security Now Available in Prebid.js

If you sell ads with Prebid.js, you can now filter bots and invalid traffic before the auction, using a standard Prebid build. The Transfon Security module became part of Prebid.js in version 11.46.0, released on 30 October 2026.

Why it matters

Bots and automated browsers load pages just like real visitors. When they trigger ad auctions, advertisers pay for impressions nobody sees, and over time they lower their bids on your site. Filtering that traffic out protects both your revenue and your reputation with buyers.

What the module does

Before each auction, the module checks whether the page view comes from a real person or from invalid traffic. It then shares that verdict with your demand partners and your ad server:

• Demand partners can bid with more confidence on traffic marked as real.
• Your ad server can keep direct deals and house campaigns away from bots.
• If you choose, the module can stop bid requests for bot traffic entirely, so bots never reach your buyers.

Your Transfon Security dashboard shows how much of your Prebid traffic is invalid and why it was flagged.

Safe for your revenue

The module never holds up the auction. If a verdict isn't ready in time, the auction runs as normal, so real visitors always see ads. It is lightweight, respects your visitors' consent choices, and works with Google Ad Manager and other major ad servers.

We recommend starting in monitoring mode: check how much invalid traffic your dashboard reports, then switch on blocking once the numbers look right for your site.

How to set it up

1. Create a Transfon Security project to get your license.
2. Share the Prebid module setup guide with your ad ops or development team. Setup is a small change to your Prebid configuration.

If your Prebid setup runs through BiddingStack, you don't need the module: the BiddingStack IVT filter does the same check with one project setting.

More from Transfon Security

The RTD module covers your Prebid auctions. The rest of Transfon Security protects the whole site, from the first page view to login, checkout and your APIs:

• Publishers: filter invalid traffic before bidding, keep scrapers and AI crawlers away from your content, and report on real visitors only. See Transfon Security for publishers.
• Advertisers: keep click bots and competitor clicks away from your campaigns on Google Ads and social platforms, so your budget goes to real people. See Transfon Security for advertisers.
• E-commerce: block scrapers, credential stuffing and checkout bots before they reach your store and customers. See Transfon Security for e-commerce.
• APIs and SaaS: stop API abuse, DDoS attacks and unauthorised access at the edge. See Transfon Security for APIs.

Every project gets traffic analytics that separate real visitors from good bots, such as search engine crawlers, and from bad ones, so you can see what is hitting your site and why it was blocked.

Get started

Sign up for Transfon Security to get a license, or contact us and we'll help you set it up.