Google faced another regulatory challenge on Monday when Turkish authorities opened an investigation into whether the search giant’s popular Android software had broken the country’s antitrust rules.
The investigation in Turkey is the latest legal problem for Google, which faces three separate competition charges in Europe and has already been found to breach antitrust legislation in Russia. United States officials have also investigated the company over its Android and search services, but they have not brought a case.
Google denies that it has broken any laws, saying that its digital services like search and online maps do not hinder those of rivals.
The number of regulatory investigations worldwide represents a growing threat for the company, just as other Silicon Valley giants like Facebook and Amazon increasingly challenge Google in the race to create new tech gadgets and digital services.
This is not the first time that Google has faced setbacks in Turkey. Over the past few years, the country’s president, Recep Tayyip Erdogan, has repeatedly blocked YouTube, Google’s popular video service, and social networks — services often used by opponents of Mr. Erdogan to share their dissent.
The new Turkish investigation relates to how Google provides some of its digital services as part of a package of software related to Android, the mobile operating system that powers more than 75 percent of the smartphones worldwide.
The complaint was filed last year by Yandex, a Russian competitor to Google. Yandex has charged that makers of cellphones are obliged to use Google’s services if they want to use the latest version of Android, but that such obligations are unfair because they create an uneven playing field.
The regulator, the Turkish Competition Authority, had initially declined to investigate Yandex’s complaint, but it said on Monday that it would look at whether Google’s use of Android to promote its other digital services infringed on the country’s competition rules. It is unclear how long the investigation will take.
That inquiry by the European Commission, the executive arm of the European Union, focused on a Google requirement that some cellphone manufacturers preinstall the company’s services, including its Google Play smartphone app store. The commission also found that Google had given the companies unfair financial incentives to favor its services on their mobile devices.
“Google has abused its dominant position,” Margrethe Vestager, Europe’s competition chief, said last year when announcing the charges against Google. The company’s “behavior has harmed consumers by restricting innovation in the wider mobile space.”