An Android smartphone displays the Google website in this picture illustration in Seoul September 7, 2011. Antitrust officials in South Korea raided Google Inc's Seoul offices on Tuesday, according to a source familiar with the matter, expanding worldwide regulatory pressure on the Internet giant. In April, South Korea's top Internet portals filed a complaint with antitrust regulators alleging that Google was unfairly stifling competition in the mobile search market. In their joint complaint, NHN Corp and Daum Communications Corp said Android smartphones have Google's search engine installed as a default navigation tool and are "systematically designed" to make it virtually impossible to switch to another option. REUTERS/Truth Leem (SOUTH KOREA - Tags: BUSINESS) 

An Android smartphone displays a Google search bar in this picture illustration in Seoul September 7, 2011. Antitrust officials in South Korea raided Google Inc's Seoul offices on Tuesday, according to a source familiar with the matter, expanding worldwide regulatory pressure on the Internet giant. In April, South Korea's top Internet portals filed a complaint with antitrust regulators alleging that Google was unfairly stifling competition in the mobile search market. In their joint complaint, NHN Corp and Daum Communications Corp said Android smartphones have Google's search engine installed as a default navigation tool and are "systematically designed" to make it virtually impossible to switch to another option. REUTERS/Truth Leem (SOUTH KOREA - Tags: BUSINESS) 

European Union Competition Commissioner Joaquin Almunia gestures during a news conference at the EU Commission headquarters in Brussels December 5, 2012. EU antitrust regulators have not yet made a decision in their case against Google and talks are proceeding with the Internet search firm to resolve complaints that it used its clout to block rivals, the EU's competition chief said. REUTERS/Laurent Dubrule (BELGIUM - Tags: POLITICS BUSINESS) 

European Union Competition Commissioner Joaquin Almunia speaks during a news conference at the EU Commission headquarters in Brussels February 5, 2014. Google agreed to make concessions on how it displays competitors' links on its website on Wednesday, in a deal with the European Union regulator that ended a three-year antitrust probe and avoided a fine. The agreement means the world's dominant search engine has avoided a process that could have lead to a fine of up to $5 billion, or 10 percent of its 2012 revenue. It must stick to the deal for the next five years. REUTERS/Francois Lenoir (BELGIUM - Tags: POLITICS SCIENCE TECHNOLOGY BUSINESS) 

European Union Competition Commissioner Joaquin Almunia speaks during a news conference at the EU Commission headquarters in Brussels February 5, 2014. Google agreed to make concessions on how it displays competitors' links on its website on Wednesday, in a deal with the European Union regulator that ended a three-year antitrust probe and avoided a fine. The agreement means the world's dominant search engine has avoided a process that could have lead to a fine of up to $5 billion, or 10 percent of its 2012 revenue. It must stick to the deal for the next five years. REUTERS/Francois Lenoir (BELGIUM - Tags: POLITICS SCIENCE TECHNOLOGY BUSINESS HEADSHOT) 

European Union Competition Commissioner Joaquin Almunia speaks during a news conference at the EU Commission headquarters in Brussels February 5, 2014. Google agreed to make concessions on how it displays competitors' links on its website on Wednesday, in a deal with the European Union regulator that ended a three-year antitrust probe and avoided a fine. The agreement means the world's dominant search engine has avoided a process that could have lead to a fine of up to $5 billion, or 10 percent of its 2012 revenue. It must stick to the deal for the next five years. REUTERS/Francois Lenoir (BELGIUM - Tags: POLITICS SCIENCE TECHNOLOGY BUSINESS) 

European Competition Commissioner Margrethe Vestager addresses a news conference at the EU Commission headquarters in Brussels April 15, 2015. Google Inc said on Wednesday it strongly disagreed with the European Commission which accused the U.S. company of distorting Internet searches in its favor and launched an antitrust probe into its mobile operating system Android. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference at the EU Commission headquarters in Brussels April 15, 2015. Google Inc said on Wednesday it strongly disagreed with the European Commission which accused the U.S. company of distorting Internet searches in its favor and launched an antitrust probe into its mobile operating system Android. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference at the EU Commission headquarters in Brussels April 15, 2015. Google Inc said on Wednesday it strongly disagreed with the European Commission which accused the U.S. company of distorting Internet searches in its favor and launched an antitrust probe into its mobile operating system Android. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference at the EU Commission headquarters in Brussels April 15, 2015. Google Inc said on Wednesday it strongly disagreed with the European Commission which accused the U.S. company of distorting Internet searches in its favor and launched an antitrust probe into its mobile operating system Android. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference at the EU Commission headquarters in Brussels April 15, 2015. Google Inc said on Wednesday it strongly disagreed with the European Commission which accused the U.S. company of distorting Internet searches in its favor and launched an antitrust probe into its mobile operating system Android. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference at the EU Commission headquarters in Brussels April 15, 2015. Google Inc said on Wednesday it strongly disagreed with the European Commission which accused the U.S. company of distorting Internet searches in its favor and launched an antitrust probe into its mobile operating system Android. REUTERS/Francois Lenoir TPX IMAGES OF THE DAY

European Competition Commissioner Margrethe Vestager addresses a news conference at the EU Commission headquarters in Brussels April 15, 2015. Google Inc said on Wednesday it strongly disagreed with the European Commission which accused the U.S. company of distorting Internet searches in its favor and launched an antitrust probe into its mobile operating system Android. REUTERS/Francois Lenoir

A woman hovers a mouse over the Google and European Union logos in Sarajevo, in this April 15, 2015 photo illustration. The European Union accused Google Inc on Wednesday of cheating competitors by distorting Internet search results in favour of its Google Shopping service and also launched an antitrust probe into its Android mobile operating system. This logo has been updated and is no longer in use. REUTERS/Dado Ruvic 

Google and European Union logos are seen in Sarajevo, in this April 15, 2015 photo illustration. The European Union accused Google Inc on Wednesday of cheating competitors by distorting Internet search results in favour of its Google Shopping service and also launched an antitrust probe into its Android mobile operating system. This logo has been updated and is no longer in use. REUTERS/Dado Ruvic 

A logo is pictured at Google's European Engineering Center in Zurich April16, 2015. The European Union accused Google Inc on Wednesday of cheating competitors by distorting Internet search results in favour of its Google Shopping service and also launched an antitrust probe into its Android mobile operating system. This logo has been updated and is no longer in use. REUTERS/Arnd Wiegmann 

A man walks past a logo at Google's European Engineering Center in Zurich April16, 2015. The European Union accused Google Inc on Wednesday of cheating competitors by distorting Internet search results in favour of its Google Shopping service and also launched an antitrust probe into its Android mobile operating system. This logo has been updated and is no longer in use. REUTERS/Arnd Wiegmann 

A logo is pictured at Google's European Engineering Center in Zurich April16, 2015. The European Union accused Google Inc on Wednesday of cheating competitors by distorting Internet search results in favour of its Google Shopping service and also launched an antitrust probe into its Android mobile operating system. This logo has been updated and is no longer in use. REUTERS/Arnd Wiegmann 

European Union Commissioner for Competition Margrethe Vestager holds a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition Margrethe Vestager holds a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition Margrethe Vestager holds a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition Margrethe Vestager pauses during a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition Margrethe Vestager holds a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition Margrethe Vestager holds a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition, Margrethe Vestager, holds a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition, Margrethe Vestager, holds a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition, Margrethe Vestager, holds a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition, Margrethe Vestager, photographs the media at the conclusion of a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

European Union Commissioner for Competition, Margrethe Vestager, photographs the media at the conclusion of a news conference at the EU Delegation in Washington April 16, 2015. The EU accused Google Inc. on Wednesday of cheating consumers and competitors by distorting web search results and also launched an antitrust probe into the internet search giant's Android system. REUTERS/Gary Cameron

Euro coins are seen in front of displayed logo of Gazprom in this picture illustration taken in Zenica, April 21, 2015. The European Union will launch a legal attack on Russian gas giant Gazprom this week, ramping up tensions with Moscow, when antitrust agents will accuse it of overcharging buyers in eastern Europe, EU sources told Reuters on Monday. The state-controlled company, a vital supplier of energy to Europe despite frequent political disputes, could receive a full charge sheet from European Competition Commissioner Margrethe Vestager on Wednesday, one source said. More than two years after Brussels started investigating Gazprom, the move comes just a week after the new EU antitrust chief charged U.S. tech giant Google with abusing its market power after five years of hesitation by her predecessor. REUTERS/Dado Ruvic 

Euro coins are seen in front of displayed logo of Gazprom in this picture illustration taken in Zenica, April 21, 2015. The European Union will launch a legal attack on Russian gas giant Gazprom this week, ramping up tensions with Moscow, when antitrust agents will accuse it of overcharging buyers in eastern Europe, EU sources told Reuters on Monday. The state-controlled company, a vital supplier of energy to Europe despite frequent political disputes, could receive a full charge sheet from European Competition Commissioner Margrethe Vestager on Wednesday, one source said. More than two years after Brussels started investigating Gazprom, the move comes just a week after the new EU antitrust chief charged U.S. tech giant Google with abusing its market power after five years of hesitation by her predecessor. REUTERS/Dado Ruvic 

Euro coins are seen in front of a Google logo in this picture illustration taken in Zenica, April 21, 2015. The European Union accused Google Inc on Wednesday of cheating competitors by distorting Internet search results in favour of its Google Shopping service and also launched an antitrust probe into its Android mobile operating system. This logo has been updated and is no longer in use. REUTERS/Dado Ruvic 

Euro coins are seen in front of a Google logo in this picture illustration taken in Zenica, April 21, 2015. The European Union accused Google Inc on Wednesday of cheating competitors by distorting Internet search results in favour of its Google Shopping service and also launched an antitrust probe into its Android mobile operating system. This logo has been updated and is no longer in use. REUTERS/Dado Ruvic 

European Competition Commissioner Margrethe Vestager addresses a news conference in Brussels, Belgium, April 20, 2016, REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference in Brussels, Belgium, April 20, 2016. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference in Brussels, Belgium, April 20, 2016. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference in Brussels, Belgium, April 20, 2016. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference in Brussels, Belgium, April 20, 2016. REUTERS/Francois Lenoir

European Union flags flutter outside the EU Commission headquarters in Brussels, Belgium, April 20, 2016. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager addresses a news conference in Brussels, Belgium, April 20, 2016. REUTERS/Francois Lenoir

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager arrives to address a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager arrives to address a news conference at the EU Commission headquarters in Brussels, Belgium, July 14, 2016. REUTERS/Francois Lenoir 

A woman holds her smart phone, which displays the Google home page, in this picture illustration taken February 24, 2016. REUTERS/Eric Gaillard/Illustration/File Photo 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission's headquarters in Brussels, Belgium, June 27, 2017. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager takes a photograph as she holds a news conference at the EU Commission's headquarters in Brussels, Belgium, June 27, 2017. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission's headquarters in Brussels, Belgium, June 27, 2017. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager takes a photograph as she holds a news conference at the EU Commission's headquarters in Brussels, Belgium, June 27, 2017. REUTERS/Francois Lenoir TPX IMAGES OF THE DAY 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission's headquarters in Brussels, Belgium, June 27, 2017. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager takes a photograph as she holds a news conference at the EU Commission's headquarters in Brussels, Belgium, June 27, 2017. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager takes a photograph as she holds a news conference at the EU Commission's headquarters in Brussels, Belgium, June 27, 2017. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission's headquarters in Brussels, Belgium, June 27, 2017. REUTERS/Francois Lenoir 

European Competition Commissioner Margrethe Vestager holds a news conference at the EU Commission's headquarters in Brussels, Belgium June 27, 2017. REUTERS/Francois Lenoir