King tried to trademark "Candy," Apple tried to trademark "app store" and now Google is trying to trademark "Glass."

The tech giant wants the trademark, of course, for its Google Glass eyewear. It already has the trademark for "Google Glass," but is seeking an additional trademark for the word "Glass" by itself, styled in the futuristic font Google uses in its packaging and marketing.

According to The Wall Street Journal, however, the U.S. Patent and Trademark Office (USPTO) is putting a kink in the company's plans. The Journal posted a letter [PDF] from the USPTO to Google, which outlines some of the problems the office has with the request.

Image: Google

The first issue is that the Glass trademark might be too similar to other glass trademarks or pending trademarks since, as it turns out, Google's not the first company to apply for a glass trademark. It's not even the first computer software/hardware related glass trademark application on file. The letter from the USPTO includes various approved or pending applications for design marks such as "glass," "looking glass," "iGlass," "smartglass" and "teleglass."

The second issue is that even if Google got a trademark on Glass — distinctive font and all — the USPTO doesn't think glass is a term that can be trademarked under federal law, which says that you can't trademark words that describe a product. It also sees "glass" as "merely descriptive."

Naturally, Google disagrees. The company reportedly filed a response to the USPTO arguing that a Google trademark of Glass would not be confusing because of how much publicity surrounds the Google Glass product.

Google also takes issue with the idea that Glass is descriptive, because Google Glass itself doesn't actually contain any physical glass.

Although King, the company that made Candy Crush Saga successfully got a U.S. trademark for the term "Candy" in mid-January, the company filed to abandon the trademark just a month later. King still retains an EU trademark on the word candy.

When Apple tried to apply for a trademark over "app store" in 2011, several courts blocked Apple's attempts to sue companies such as Amazon for trademark infringement.

No word on whether Google will apply for a trademark of the word "Glasshole" next.