The BBC reports:
Twitter has apologised for allowing adverts to be micro-targeted at certain users such as neo-Nazis, homophobes and other hate groups. The BBC discovered the issue and that prompted the tech firm to act.
Our investigation found it possible to target users who had shown an interest in keywords including “transphobic”, “white supremacists” and “anti-gay”. Twitter allows ads to be directed at users who have posted about or searched for specific topics.
But the firm has now said it is sorry for failing to exclude discriminatory terms. Anti-hate charities had raised concerns that the US tech company’s advertising platform could have been used to spread intolerance.