The UK Internet Advertising Bureau (IAB) has worked with the industry to launch a tool it is hoping will help brands and media agencies understand the value they derive from different adtech companies.

Dubbed 'Transparency FAQs' the online portal comprises information around pricing, placement and data – including specific details on the brand safety and GDPR practices employed by digital players.

News Corp's Unruly, 'free wall' business Rezonance and Rubicon Project are among those to have volunteered information.

The launch from the IAB follows on from a report from Warc last year which analysed global ad spend data and concluded that over $30bn of the $63.4bn spent on programmatic ads last year wound up in the hands of tech vendors or 'middlemen'. The study said this so-called 'tech tax' (not to be confused with the EU's impending 'tech tax on the likes of Facebook) accounted for 55% of all programmatic spend in 2017.

Transparency FAQs also comes amid calls from the likes of Unilever, P&G and more to see where their ad budgets are really being spent.

The IAB said that while it appreciated the difficulty advertisers faced in unpicking the contribution of different adtech firms, that bundling of every company between buyer and seller as a 'tax' was "misleading".

As such, the questions featured on the IAB's platform were produced by a panel of 20 members from across the industry.

20 'common' queries, including ' do you own the inventory you sell' and 'do you have a policy in place for ad misplacement?' have been answered by adtech outfits in order to equip brands and their agencies with intel around companies' wider business models and provide an insight into their attitude towards transparency.

The Incorporated Society of British Advertisers (ISBA) and The Institute of Practitioners in Advertising (IPA) welcomed the move, which follows on from the IAB introducing a 'Gold Standard' for digital companies last year.

Tim Elkington, chief digital officer at IAB UK, said: "The Transparency FAQs is a voluntary initiative that we hope ad tech companies will embrace as they will help buyers understand the landscape more easily. They’re not a silver bullet or cure for issues around transparency, but we think they’re a useful step forward."

He went on: "The answers to the FAQs will enable buyers to compare the policies and attitudes of ad tech companies in the same way that you might use the John Lewis site to compare vacuum cleaners before making a purchase."