What kinds of accounts get verified?

Twitter proactively verifies accounts on an ongoing basis to make it easier for users to find who they’re looking for. We concentrate on highly sought users in music, acting, fashion, government, politics, religion, journalism, media, advertising, business, and other key interest areas. We verify business partners from time to time and individuals at high risk of impersonation.

We do not accept requests for verification from the general public. If you fall under one of the above categories and your Twitter account meets our qualifications for verification, we may reach out to you in the future.
Source: Twitter