The USPTO cited in its decision all the companies that use "tweet" in their titles, suggesting that a trademark of the root word would add to confusion.
Twitter will have a chance to appeal the decision, however, and promised not to lord it over those other companies if the trademark is ever approved.
And in an interview last week, co-founder Biz Stone told technology news site VentureBeat that Twitter is already testing a new system that would allow businesses to pay for accounts.
The paid accounts would likely come with new features, such as statistics and software tools, that are not currently available.
With a total of $55 million in funding from venture capitalists, the company could afford to take its time actually coming up with a way to make money.
Photo by Joi Ito.
Jackson West hasn't update his Twitter stream in days. Days!