Axel Springer just scored a huge victory in court against Adblock Plus

A German court on Friday handed publisher Axel Springer - the parent company of Business Insider, Bild, and Die Welt - a material win in its fight against ad blockers, which users can install on computers or mobile devices to prevent advertising from being shown.

The appeals court in Cologne on Friday banned German startup Eyeo, the parent company of Adblock Plus, from charging Axel Springer a fee to appear on its "Acceptable Ads" whitelist.

The whitelist lets companies that submit advertising to Eyeo, which is not deemed to be annoying or intrusive, to have their ads served to Adblock Plus' users.

Large entities, such as Google and Criteo, are charged 30% of the additional revenue created for having those ads whitelisted.

Now, the court ruled that Axel Springer will not have to pay to appear on the whitelist, which could open the floodgates to the many other large entities taking Eyeo to court on this matter too - at least in Germany, where 25.3% of internet users have ad blockers, according to a 2015 report from PageFair and Adobe.

In a blog post, Eyeo says it plans to appeal the ruling: "And we're confident that Germany's supreme court (the Bundesgerichtshof) will overturn this one part of the decision."

The appeals court ruled it did not have objections to ad blocker usage, but agreed with Axel Springer that the Acceptable Ads list arrangement was in breach of German unfair competition law.

Adblock Plus explained in its blog post:

Axel Springer's attorneys used this sub-clause [Paragraph 4a UWG] to justify their secondary request to the court: "to ban an adblocker if that ad blocker allows ads that meet certain criteria and requires that Springer [emphasis mine] needs to pay a fee for it."

Now, the Acceptable Ads initiative to which this obliquely refers is completely fair and utterly transparent. What it provides is a way for publishers and advertisers, if they so choose, to reach ad blockers on their terms.

Last September, a German court said that Adblock Plus does not breach laws on competition, copyright, or market dominance - the arguments first brought by Axel Springer, which went on to appeal.

(Reporting by Lara O'Reilly, Business Insider and from Reuters: Nikola Rotscheroth; Writing by Harro ten Wolde; Editing by Georgina Prodhan)

Disclosure: Axel Springer is Business Insider's parent company.