After a five-and-a-half-year fight, Google and its attorneys have managed to convince federal bureaucrats to bestow a patent on the company’s iconic home page. We always thought the page was brain-dead simple, but apparently it’s an innovative “graphical user interface.”

Google had more luck patenting the design of its search results, which were submitted along with the home page in early 2004 and cleared the U.S. Patent and Trademark Office at the end of 2006. The home page, in contrast, was split off into a separate application, receiving its design patent for a “Graphical user interface for a display screen of a communications terminal” just yesterday. The document (see below) is as minimalist as the interface, containing a single illustration of Google.com, with the company logo depicted in dotted lines to indicate it is not an integral part of the patent.

In other words, subject to how the patent is enforced, Google owns the idea of having a giant search box in the middle of the page, with two big buttons underneath and several small links nearby. Since the time of the patent application in 2004, the company has moved some links, for searching News and Groups and other alternate databases, from directly above the search box to the top of the home page. But Google presumably believes its patent is broad enough to cover the variation.

It’s not clear how the company, already under scrutiny from antitrust regulators, will wield the patent against competitors. The Yahoo Search page, depicted at left, bears a striking resemblance to Google.com, while Microsoft’s Bing, which features a photo and several headlines, is more distinct. But there mere existence of the patent should create enough uncertainty to scare some worried startups away from Google’s stripped down look. So while people may flock to the search engine for its clean, minimalist design, in so doing they are supporting a company that is poised to retard the spread of such an aesthetic online.

Google’s shareholders will be more pleased, of course, as will staff. Google diva Marissa Mayer, the overachieving VP of search, added another patent to her trophy case with the decision. Powerful executive; athlete; fashionista; and genius inventor of this totally unprecedented rendering of HTML. Is there anything Mayer can’t do?