Popular picture sharing site Twitpic announced today that it would be shutting down on September 25 after a dispute with Twitter. Twitpic says that Twitter gave the picture host an ultimatum: either drop a 2009 trademark on the term "Twitpic," or lose access to the Twitter API. This loss of access would prevent the easy tweeting of pictures posted to Twitpic.

The company has accordingly decided that rather than cede the trademark it will go out of business. Twitpic founder Noah Everett wrote that trademark application had to face a number of difficulties, the last of which was only recently overcome. Twitter issued its threat during the "published for opposition" phase of the trademark application.

Twitter writes that it is "sad to see Twitpic is shutting down" and notes that it was fine for the sharing service to "operate using the Twitpic name." Twitter's opposition to the trademark was a necessary move to "protect its brand." While Twitpic could plainly have continued to operate without the trademark, giving it up would allow others to also use the Twitpic name.

Twitpic was created at a time when Twitter had no image hosting of its own. The only way to share pictures on the short message service was to host them elsewhere, and then tweet a link. Twitpic simplified this task, as did a number of similar services such as ImageShack's yfrog and Photobucket's TinyPic. However, the necessity of services like Twitpic was greatly diminished when Twitter added the ability to directly host images on Twitter, and integrated picture uploading into its clients.

Twitpic says that it is going to introduce some facility for soon-to-be-former users to export all the images they uploaded and save them elsewhere. However, the impact is going to be substantial, as any historic tweets that link to Twitpic will be broken.