La oss ta en titt på Twitters personvernerklæring («Privacy Policy») (av 18. juni 2017). Alle sitatene nedenfor stammer fra denne med mindre annet oppgis.

Hvis en gir Twitter tilgang til kontaktene sine (i Gmail, Outlook e.l.), kan denne informasjonen bli brukt til å tilpasse tjenesten (altså Twitter) for denne brukeren. Velger brukeren å slette kontaktene, slettes de antakeligvis også i Twitters database; heller tvilsomt er det at også alt Twitter har avledet av disse opplysningene, slettes:

You may choose to provide us with additional information to help improve and personalize your experience across our Services. For example, you may choose to upload and sync your address book so that we can help you find and connect with users you know or help other users find and connect with you. We may later personalize content, such as making suggestions or showing user accounts and Tweets for you and other users, based on imported address book contacts. You can delete your imported address book contacts at any time by visiting your Contacts Dashboard at https://twitter.com/settings/contacts_dashboard.

Alt en publiserer på Twitter, kan bli brukt til analyse. Dette er en selvfølge; det er åpent tilgjengelig. Men hva med beskyttede tweets («protected Tweets») og annet som ikke offentliggjøres? Analyserer Twitter slikt i samme grad? (Om direktemeldinger står det lenger nede: «We do not use the content you share privately in Direct Messages to serve you ads.»)

Most of the information you provide us through Twitter is information you are asking us to make public. […] When you share information or content like photos, videos, and links via the Services, you should think carefully about what you are making public. We may use this information to make inferences, like what topics you may be interested in. Our default is almost always to make the information you provide through the Services public for as long as you do not delete it, but we generally give you settings or features, like protected Tweets, to make the information more private if you want.

En kan selv velge om en vil publisere stedsopplysninger på Twitter. Men uavhengig av dette samler og lagrer Twitter ivrig stedsinformasjon, bare begrenset av hva som meddeles av enheten en bruker (f.eks. en smarttelefon):

We may receive information about your location. For example, you may choose to publish your location in your Tweets and in your Twitter profile. You may also tell us your location when you set your trend location on Twitter.com. We may also determine location by using other data from your device, such as precise location information from GPS, information about wireless networks or cell towers near your mobile device, or your IP address. We may use and store information about your location to provide features of our Services, such as allowing you to Tweet with your location, and to improve and customize the Services, for example, with more relevant content like local trends, stories, ads, and suggestions for people to follow.

Twitter registrerer hvilke lenker en klikker på. Det finnes ingen enkel måte å omgå dette på fordi alle lenker på Twitter blir forkortet til t.co-lenker:

We may keep track of how you interact with links across our Services, including our email notifications, third-party services, and client applications, by redirecting clicks or through other means. We do this to help improve our Services, to provide more relevant advertising, and to be able to share aggregate click statistics such as how many times a particular link was clicked on. Links, Tweets, and non-public communications like Direct Messages shared on the Services will be processed and links shortened to a http://t.co link.

Informasjonskapsler brukes selvsagt til sporing. En kan til en viss grad styre dette selv (men se nedenfor). Twitter støtter ikke lenger Do Not Track-innstillingen:

We may use both session cookies and persistent cookies to better understand how you interact with our Services, to monitor aggregate usage by our users and web traffic routing on our Services, and to customize and improve our Services. […] You can control how we personalize your Twitter experience and ads by using your Personalization and Data settings, which are available at https://twitter.com/personalization whether or not you have a Twitter account. We respond to these settings rather than the Do Not Track browser option, which we no longer support.

Twitter samler opplysninger om det meste en foretar seg som har noen tilknytning til tjenesten. En har som sagt en viss kontroll over «Personlig tilpasning og data». En kan bestemme om Twitter kan «del[e] data via utvalgte samarbeidspartnere» («men aldri navnet ditt, e-postadressen din eller telefonnummeret ditt»). «Partnerne har godtatt at navnet ditt, e-postadressen din og telefonnummeret ditt ikke skal knyttes til dataene via disse samarbeidene uten uttrykkelig tillatelse fra deg.» Takket være EUs personvernforordning kan brukere i EØS og Sveits ikke gi Twitter tillatelse til «hold[e] oversikt over hvor på nettet [de] ser Twitter-innhold.» Bekymringsverdig er det at en tilsynelatende riktignok kan kontrollere innholdet Twitter tilpasser, men bare til en viss grad hvilke opplysninger som faktisk blir samlet inn.

På siden Twitter-dataene dine kan en se noe av det Twitter mener å vite om en: kjønn, alder(sgruppe), språk (eventuelt i flertall). Disse opplysningene kan en også velge å oppgi manuelt. I tillegg kommer interesserer en har vist på Twitter og hos «partnere» (basert på informasjon Twitter har fått fra andre), som en også til en viss grad kan tilpasse manuelt, og hvor mange målgrupper fra hvor mange annonsører en tilhører. Alt etter hva en har valgt i «Personlig tilpasning og data», kan en se hvilke enheter og hvilke apper på disse enhetene som er registrert samt «steder [en] har vært».

Twitter lagrer tidspunktet og IP-adressen som ble brukt da kontoen ble opprettet samt tid og sted (IP-adresse) for de siste 50 (?) innloggingene fra apper og på https://mobile.twitter.com. Loggdata slettes eller anonymiseres senest etter 18 måneder, står det, men det er verdt å merke seg at dette ikke gjelder tidspunktet og IP-adressen som ble brukt da kontoen ble opprettet:

We receive information when you view content on or otherwise interact with our Services, even if you have not created an account (“Log Data”). For example, when you visit our websites, sign into our Services, interact with our email notifications, use your account to authenticate to a third-party website, application, or service, or visit a third-party website, application, or service that includes Twitter content, we may receive information about you. This Log Data may include your IP address, browser type, operating system, the referring web page, pages visited, location, your mobile carrier, device information (including device and application IDs), search terms, or cookie information. We also receive Log Data when you click on, view or interact with links on our Services, including links to third-party applications, such as when you choose to install another application through Twitter. We use Log Data to make inferences, like what topics you may be interested in, and to customize the content we show you, including ads. You can learn about the interests we have inferred about you from your activity on and off of Twitter in Your Twitter Data, available at https://twitter.com/your_twitter_data. We keep Log Data as needed for the purposes described in this Privacy Policy. We will either delete Log Data or remove any common account identifiers, such as your username, full IP address, email address, or phone number, after a maximum of 18 months, if not sooner.

Twitter bruker opplysninger fra tredjeparter:

Our ad partners and affiliates may share information with us such as a browser cookie ID, mobile device ID, or cryptographic hash of an email address, as well as demographic or interest data and content viewed or actions taken on a website or app. Our ad partners, particularly our advertisers, may enable us to collect similar information directly from their website or app by integrating our advertising technology.

Twitter kan samle opplysninger fra enheter og nettlesere en ikke bruker twitter på/i dersom en tillater det:

Depending on your settings, we may also personalize your experience on, and based on information from, other browsers or devices besides the ones you use to log into Twitter. For example, if you visit websites with sports content on your laptop, we may show you sports-related ads on Twitter for Android.

Twitter forbeholder seg retten til å utlevere alle ens opplysninger i en god del tilfeller:

Notwithstanding anything to the contrary in this Privacy Policy, we may preserve or disclose your information if we believe that it is reasonably necessary to comply with a law, regulation, legal process, or governmental request; to protect the safety of any person; to address fraud, security or technical issues; or to protect our or our users’ rights or property. However, nothing in this Privacy Policy is intended to limit any legal defenses or objections that you may have to a third party’s, including a government’s, request to disclose your information.

Opplysningene kan bli overført til andre, om enn samme personvernvilkår vil gjelde (inntil videre). Opplysninger kan bli delt med andre selskaper i samme familie, som har egne personvernerklæringer, tydeligvis uten begrensninger.

In the event that we are involved in a bankruptcy, merger, acquisition, reorganization or sale of assets, your information may be sold or transferred as part of that transaction. This Privacy Policy will apply to your information as transferred to the new entity. We may also disclose information about you to our corporate affiliates in order to help provide, understand, and improve our Services and our affiliates’ services, including the delivery of ads.

En kan la twitter dele anonymisert informasjon med andre som eventuelt kan deanynomisere informasjonen. En slik deanynomisering forutsetter et ytterligere samtykke fra brukeren.

We may […] share non-personal, aggregated, or device-level information through partnerships with entities that may use data in their possession (including data you may have given them) to link your name, email address, or other personal information to the information we provide them. These partnerships require that they get your consent before doing so. You can control whether Twitter shares your information under these partnerships by using your Personalization and Data settings, available at https://twitter.com/personalization.

En kan slette kontoen sin. Det virker som dette betyr at også alle tilknyttede opplysninger blir slettet eller anonymisert.

You can also permanently delete your Twitter account. If you follow the instructions here, your account will be deactivated and then deleted. When deactivated, your account, including your name, username, and public profile, is not viewable on Twitter.com. For up to 30 days after deactivation it is still possible to restore your account if it was accidentally or wrongfully deactivated. Absent a separate arrangement between you and us to extend your deactivation period, after 30 days, we begin the process of deleting your account from our systems, which can take up to a week.

Personvernerklæring kan bli endret, men brukeren får beskjed. Videre bruk av tjenesten gjelder da som samtykke.

We may revise this Privacy Policy from time to time. The most current version of the policy will govern our use of your information and will always be at https://twitter.com/privacy. If we make a change to this policy that, in our sole discretion, is material, we will notify you via an @Twitter update or email to the email address associated with your account. By continuing to access or use the Services after those changes become effective, you agree to be bound by the revised Privacy Policy.