Twitter says it unintentionally misused user data for advertising

Twitter disclosed Tuesday that it "unintentionally" used some email addresses and phone numbers for advertising even though the information was provided for account security.

Why it matters: It's the latest example of a tech company misusing user data.

"We cannot say with certainty how many people were impacted by this, but in an effort to be transparent, we wanted to make everyone aware. No personal data was ever shared externally with our partners or any other third parties."

But but but: The information was used to help tailor which advertising some users saw.

"As of September 17, we have addressed the issue that allowed this to occur and are no longer using phone numbers or email addresses collected for safety or security purposes for advertising."

• It's not immediately clear why Twitter is only now notifying users.

Meanwhile: While in Twitter's case the use was accidental, Facebook intentionally used phone numbers provided for security to target ads — at least until the FTC complained.