More and more companies are using Twitter and other social media sites to promote their businesses. Often, an employee or a group of employees will have the job of tweeting regularly about the company’s products and services.

However, this raises the question of what happens if an employee with a Twitter account quits or is fired.

The issue came up recently when an employee named Noah Kravitz started tweeting for his employer, a company called PhoneDog.com. As part of the company’s efforts to drive traffic to its website, Kravitz sent his followers his opinions of new mobile phones on the market, as well as some other topics. Kravitz proved to be very popular, and eventually attracted 17,000 followers of his tweets.

When Kravitz quit his job, he changed his Twitter handle, but he kept the same account and password, effectively taking all 17,000 followers with him.

PhoneDog then sued him for “misappropriation of trade secrets,” claiming that the account and the password were confidential, proprietary information, similar to a customer list. PhoneDog demanded $340,000 in damages.

Kravitz fired back, arguing that the 17,000 followers weren’t “secrets,” and that a Twitter password by itself has no “independent economic value.”

Who’s right? It won’t be clear unless the case goes to trial, but if you have employees who use Twitter to expand your business, you might want to adopt a policy or add a clause to your employment agreements clarifying the rights to the accounts and passwords in the event that an employee leaves the company. Such a policy or clause might not prevent all disputes, but it could be very helpful if one does arise.