Google rivals' complaints explained
The European Union has accused Google of indulging in unfair competition by giving its own Shopping service prominence over others' links in its search results.
The EU's competition commissioner said this constituted an "abuse" of its position as the dominant search service in the 28-country bloc.
Google "strongly disagrees" with the charge and says its service does not distort the market.
While the allegation is limited to the ads Google places at the top and right-hand side of its results, a ruling against the firm could set a precedent by which other complaints would be judged.
Many of the US firm's rivals have long complained that Google unfairly favours a range of services that it owns.
The BBC's technology correspondent Rory Cellan-Jones gives some examples in the clip above.