The phone number you provide to Twitter for additional security is only meant to be used for two-factor authentication. But as it turns out, the social network had been “unintentionally” using it for more.
Twitter has admitted in a blog post on Tuesday that it had been using personal email addresses and phone numbers for targeted ads. This issue stemmed from the social network’s tailored audiences program, where advertises can customize promos based on uploaded marketing lists.
Twitter says that it may have matched the people to the marketing lists based on their phone numbers and addresses, something which is supposed to be off-limits.
Twitter officially apologized saying it was an “error” and that they are taking steps to make sure such a mistake never happens again. The company says it never shared any personal data and that the issue has been resolved as of September 17th.
Whether this was unintentional or not, the effect is the same, sensitive account details were being used for ad targeting without the users’ knowledge. This puts Twitter on the same boat as Facebook which also caught flak last year for using phone numbers for ad targeting.
Regulators might decide to investigate more into the matter and slap fines onto Twitter the same way they did to Facebook.