Verified Twitter accounts are coveted and increasingly scarce commodities. That's partly why the story of an imposter of Rupert Murdoch's wife, Wendi Deng, getting "verified" by Twitter blew up on the web last week. (It turned out to be a simple case of human error.)

Those little blue "verified" check marks have become status symbols. And while verified accounts aren't officially for sale, Twitter advertisers who spend a minimum of $15,000 over three months can get one, according to a media publisher who has been trying to get his magazine's account verified.

Twitter launched verified accounts in June 2009. It had a public page on which users could apply that it took down in the summer of 2010. (The company cited scalability problems arising from the volume of requests.) That explains why some obscure U.S. congressional representative have verified accounts, but national political figures who rose to prominence more recently such as Christine O' Donnell and Sharron Angle don't.

There's no longer an application process that 's open to the public, but you can get a verified account if you can demonstrate that someone's willfully trying to impersonate you, or if you're a advertiser or partner, which Twitter spells out in its policies. The accounts are considered perks for advertisers using Twitter's promoted products (still an invite-only program), as well as a way to confirm the identity of advertisers writing "Promoted Tweets."

Andy Cohn, president and publisher of music magazine The Fader, found that out last week when he tried to get the title's Twitter handle --- 73,000 followers strong -- verified. When he asked a Twitter sales rep who had been in contact with him how to go about it, she replied that the only paths to verification are if an account has had impersonation issues or is an advertiser who's spent at least $15,000 over three months.

Mr. Cohn pointed out that Twitter is the primary distribution channel for Fader's digital content and that the credibility of a verified account would be invaluable. But as a small media company, it simply doesn't have the resources to spend that much on Twitter ads to get it.

"It's annoying, because I use Tweetdeck and have a column for anything using Fader, and half of these things are people tweeting links to the wrong account," Mr. Cohn said.