Because Verizon supports Comcast's Xfinity Mobile mobile virtual network operator (MVNO), Comcast "does not have access to nor does it obtain precise geolocation data ... from Verizon."

Comcast keeps whatever location information it does have for two years in most cases.

Verizon handles 911 services and law enforcement requests for Xfinity Mobile.

Comcast said subscribers cannot opt out of its data retention policies because it "retains a limited set of location data for as long as is necessary to provide services and perform the operational functions identified above; it is not used for marketing or advertising, and we do not share any Xfinity Mobile location data or Xfinity Wi-Fi location data with third parties for their own purposes."

Verizon said it collects cell site and sector location data to operate its network. The company also said its Verizon-branded applications collect data including telephone numbers and latitude/longitude coordinates. "However, many applications collect less – or none – of this data, depending on the specific uses that apps make of location," according to Verizon.

Verizon also collects location information for its Business and Marketing Insights program. "For example, we may use network location data to develop insights to help estimate traffic patterns during the morning rush hour or how many customers go to a retail store," Verizon said. "The information we use and the insights that are developed do not identify customers individually; rather, they will show things like the total number of customers that were at a stadium at a given time. Our customers can opt out of this program at any time." That data is then sold to customers of the program.

Verizon keeps location data for one year but sometimes less in certain circumstances.

"With one, limited exception, Verizon Wireless stores geolocation data for our consumer customers in the United States. There is limited storage of data associated with one application (Care Smart) in Canada in connection with the Get Help professional monitoring feature," the carrier explained.

T-Mobile collects several kinds of location data including "the current location of a handset to provide the estimated longitude and latitude (and, at times, elevation and/or street address) of the handset in response to either a customer placing a call or sending a text message to 911," according to the company.

Its policy "is not to collect or retain geolocation data for advertising purposes without affirmative customer consent," the company said. T-Mobile recently launched an advertising business.

T-Mobile keeps geolocation data for up to two years.

"Because opting-out of continued retention could undermine our essential operations, we generally do not allow customers to opt-out of the company's retention of geolocation data," the company said. "As our privacy notice explains, we do allow customers to opt-out of the use of device diagnostic information – including geolocation data – for troubleshooting and network improvement."

"T-Mobile's practice is not to sell geolocation data to third parties," the company said.

Mint Mobile collects and retains "minimal" longitude and latitude data "for the purposes of (i) determining network availability and quality around the consumer's location, (ii) phone number procurement and assignment, and (iii) to assist in troubleshooting if a subscriber using the account management app encounters an issue," according to the company. "Because the data has not been formatted or extracted into a usable format, it is currently fulfilling no other use cases."

Mint keeps geolocation data for 18 months for both existing and former subscribers.

"Our network provider does NOT disclose tower location information to us," the company said. "Our assumption is that law enforcement has the ability to triangulate subscriber location via the combination of information we provide and the information they receive from the network operator." Mint's service runs on top of T-Mobile's network.

Mint Mobile and its parent company Ultra Mobile said they do not share geolocation data with third parties.

"For Android devices, Google Fi's network-switching function, which ensures that the device uses the best available network based on the device's location, requires that the device process certain types of data–such as device location (GPS and other signals), Cell IDs, and MCCs [mobile country codes]," the company said. "However, this data, with the exception of Cell IDs, MCCs, and IP addresses, does not leave the subscriber's device."

Google said it processes data at Google data centers, "which are decentralized and located in many countries around the world. A Google Fi subscriber's data may be processed (and stored securely) at any of these data centers."

It can take up to two months and sometimes longer to delete customers' data, according to the company.

"Google Fi also shares limited types of data with Google affiliates as needed to: provide Google Fi services; process device purchases; bill and collect payments for Google Fi services and devices; troubleshoot potential issues with Google Fi services, devices, or the Google Fi account; verify identity; and protect from fraud, phishing, or other misconduct," the company said.

For its MVNO-based offerings, Dish said it "neither receives nor obtains geolocation data from the underlying facilities-based carriers that host its MVNO customers."

"There is no need for subscribers to opt out of the sharing of geolocation data specific to a customer because Dish does not share customer-identifying geolocation data with third parties except as required to comply with a valid and lawful legal process or for network optimization," Dish said. "Project Genesis will notify customers of any future sharing of their geolocation information with third parties, consistent with applicable law."

Charter's Spectrum Mobile service runs on the Verizon network. Charter explained that when a Spectrum Mobile customer connects, Verizon sends Spectrum Mobile several types of data, including identifying information for the cell sites used to start and end calls or data transmissions and data about international roaming. "Spectrum Mobile uses this information from Verizon to analyze customer traffic trends, for billing, and to provide troubleshooting and other customer service in the event of service-related issues. Verizon does not share the locations of specific cell sites or the geolocation of devices with Spectrum Mobile," the company said.

Charter said it explicitly asks customers for permission to use their geolocation information. "If a customer opts in to enable location services, an embedded Connection Manager (on Android devices) or software in the My Spectrum App or Spectrum TV App (on any device) shares geolocation information with Spectrum Mobile for the purposes of diagnosing connectivity issues, and informing network planning and engineering. The information is encrypted and retained for no more than two years in case it is needed for specific troubleshooting reasons. Senior leaders must approve any request and accompanying business purpose to access decrypted geolocation information within the two-year retention period to troubleshoot a specific service issue. After two years, geolocation information is aggregated in a way that cannot be tied to an individual user and stored for up to three years for network planning, usage analytics, and year-over-year comparisons. Spectrum Mobile customers may change their My Spectrum App, Spectrum TV App, or Connection Manager settings, or opt out of location services, at any time, regardless of their device type."

The company said it does not sell or share geolocation data with third parties for any purpose, including advertising.

"Spectrum Mobile customers do not have the ability to opt out of Charter's overall data retention policies. However, customers do have the ability to opt out or manage whether Charter collects geolocation information via their mobile devices or through our mobile applications," the company said.

AT&T said it developed a product called IQI software that is "embedded in the firmware of Android devices by original equipment manufacturers ("OEMs"). It collects device diagnostic and location data on a passive basis (e.g., when a device powers on or contacts a new cell tower), including latitude/longitude information. AT&T Mobility uses IQI software to improve network performance and for customer service purposes. For example, AT&T Mobility uses data derived from IQI software to identify areas where it needs to enhance network coverage. AT&T Mobility does not share IQI data except where legally required, nor do we use it for advertising purposes."

AT&T said it operates a Relevant Advertising business, which is an opt-out advertising program, and Enhanced Relevant Advertising, which is an opt-in advertising program.

Regarding location data, AT&T said it keeps some for 13 months or five years, depending on the type of data.

"We do not share location data with location aggregators and location-based service providers, and we would not share such data with other third parties without our customer's consent," the carrier said.

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