Google Fi, a mobile virtual network operator, reported a third-party system was breached that stored “a limited amount” of customer data, InfoSecurity Magazine reports. Stolen data reportedly included account activation dates, information about specific mobile plans and SIM card serial numbers. InfoSecurity Magazine obtained an email sent to Google Fi customers by the company, in which officials said no personally identifiable information was stolen from customers, but it did not disclose the name of the third-party service provider that sustained the data breach.