Dormant Twitter accounts not confirmed before an 11 December deadline will be closed, reports the BBC. Twitter's updating its user agreement, and if you can't agree to it, you're gone.
A spokeswoman also said it would improve credibility by removing dormant accounts from people's follower counts, something which may give a user an undue sense of importance. The first batch of deleted accounts will involve those registered outside of the US.
The firm bases inactivity on whether or not a person has logged in at least once in the past six months. Twitter said the effort is not, as had been suggested by some users on the network, an attempt to free up usernames.