Content verification tool Project Sunblock has announced its integration with AppNexus, said to be the world's largest URL category database, meaning it can vet or block advertising as it is bought or sold in real time.
The London-based firm aims to ensure brands' reputations are not tarnished by their online advertising appearing alongside embarrassing or inappropriate content such as pornography.
It said the new integration means its tool lets brands make the most of real time bidding (RTB), which is the automated buying and selling of individual ad impressions in real time, by showing what range of websites the adverts could be displayed on.
Its integration with AppNexus means Sunblock now offers the ability of pre-bid vetting, where it can analyse and respond to 40,000 ad impression inventory requests every second, monitoring and vetting URLs and blocking bids made through ad exchanges like AppNexus in around three milliseconds.
CBR revealed this new technology would feature as part of the Sunblock tool last month, and the company hopes it will give brands more autonomy over where their adverts appear, by turning down bids which would place the brands' advertising on websites featuring objectionable content.
Sunblock CEO Duncan Trigg said: "It's Project Sunblock's mission to address brand safety online and bring total transparency to the buying chain.
"The beauty of our new pre-bidding blocking service is its ability to detect what is really being offered within RTB, so that precious budget is spent only on placements with the right contextual environment.
"In tandem with this, it promotes brand safety by preventing advertising from appearing on undesirable or illegal locations on the Internet."