The European Union has been probing Google for several years amid concerns that the US internet giant may be illegally hampering competition.
Here are the different areas that the bloc's regulators are investigating. They could hit Google with hefty fines if the company is found to have violated the EU's strict competition laws and refuses to change its business practices.
ONLINE SEARCH RESULTS: The EU is concerned that Google is giving its specialized services - such as Google Maps, Google Shopping and Google Places - favourable treatment in the way it displays online search results.
The European Commission, the EU's executive, last year took a step closer to a fine on this front, formally spelling out its suspicions of misconduct relating to Google Shopping in a so-called statement of objections. On Thursday it reinforced those suspicions, citing new evidence.
The commission has taken issue with the fact that "Google's comparison shopping product is systematically displayed prominently at the top" when someone enters a shopping-related query into the search engine, regardless of relevance and at the expense of rivals.
It is still looking at other Google search services, such as those related to hotels and flights.
ANDROID: The commission last year also launched an investigation into Google's operating system for smartphones and tablets, known as Android. In April, it issued a statement of objections spelling out the Google business practices that it believes violate EU rules.
It found that manufacturers must pre-install Google's search engine and Chrome web browser on mobile devices that use any other of the company's licensed apps, such as its popular Google Play app store. This blocks competitors and limits manufacturer and consumer choices on which search engine and browser to use, the commission said.
It also accused Google of preventing manufacturers wishing to install Google apps on their devices from using competitors' modified versions of Android and of providing financial incentives to firms that offered Google Search as the exclusive search engine on their mobile devices.
"As a result of Google's behaviour, rival search engines, mobile operating systems and web browsers have not been able to compete on their merits, but rather been artificially excluded from certain business opportunities," EU Competition Commissioner Margrethe Vestager said at the time.
ADVERTISING: The EU has concerns about two practices in this area.
One relates to restrictions Google has set for third-party websites using its online search advertising to also use competing services. On Thursday, the commission issued a statement of objections spelling out why it thinks this breaches EU competition rules.
"We believe that these restrictions allowed Google to protect its very high market shares for search advertising. They hindered competition and they stifled choice and innovation, to the detriment of consumers," Vestager said Thursday.
The other has to do with Google not allowing software developers to offer tools that could make it easier to transfer search advertising campaigns from its AdWords system to that of competitors. This area is still being investigated.
CONTENT FROM THIRD PARTIES: The EU has raised concerns that Google uses content from other websites, such as user reviews and newspaper articles, in its specialized services without consent.
This area is still being investigated.