The guidelines, which take immediate effect, will be
followed up next week by the publication of draft rules that could eventually
impose further restrictions on the tech sector.
Smaller rivals and some companies have long complained about
arbitrary and opaque practices tech giants employ that affect how their
products and services are ranked in search results, especially when that means
they are placed far below the bigger companies.
Google's online search practices have landed it total fines
of more than EUR 8 billion over the period 2017-19 from EU antitrust regulators
who found it had unfairly pushed its own products to the disadvantage of
competitors.
The Commission said the guidelines require online platforms
to identify the algorithmic parameters that determine ranking and to share them
with companies.
"These guidelines set the standard for algorithmic
ranking transparency and will increase fairness in the online platform economy,
which drives innovation and welfare for millions of Europeans," European
Competition Commissioner Margrethe Vestager said in a statement.
Vestager will on December 15 present draft rules to rein in
tech giants, setting out a list of dos and don'ts and increasing their
responsibility to take down illegal and harmful content from their platforms,
with fines and other sanctions to encourage compliance.
Neither Microsoft nor Google responded immediately to
requests for comment.
© Reuters