TORONTO -- BlackBerry (TSX:BB) is suing Typo Products, a company co-founded by TV personality Ryan Seacrest, saying that its new iPhone case rips off the famous BlackBerry keyboard.

In documents filed in a California court, BlackBerry accused Typo of copying its keyboard design in an effort to capitalize on the smartphone maker's "commercial recognition and goodwill."

"Typo's keyboard product has caused and is likely to continue to cause confusion, mistake and deception as to the source of origin of (its) products," BlackBerry said in the filing.

"(It) is likely to falsely suggest a sponsorship, connection, or association between Typo, its products, and its commercial activities with BlackBerry."

Typo Products did not respond to a request for comment and none of the allegations have been proven in court.

Seacrest is the host of "American Idol," as well as the weekly countdown radio show "American Top 40," and a producer on several television shows. He founded Typo alongside entrepreneur Laurence Hallier, creator and CEO of Show Media, which sells advertising space on taxi cabs in the U.S.

The idea for the Typo keyboard was born when its founders noticed their friends were carrying two phones -- "one for typing and correspondence and an iPhone for virtually everything else," the company said on its website.

The Typo case runs on a lithium-ion battery and adds about six millimetres in thickness and less than two centimetres in length once it is attached to an iPhone 5 or 5S. The keyboard case substitutes for the touchscreen keyboard.

While the case is already available for preorder online for US$99, it will officially debut at the Consumer Electronics Show in Las Vegas next week.

BlackBerry's lawsuit comes as the company moves to protect its keyboard, one of the key differentiators between its smartphone and most other competitors on the market.

The lawsuit outlines in meticulous detail the specifics of the keyboard layout and the roots of its current design. It also highlights several industry and analyst reviews that referred to "blatant copying" of the BlackBerry keyboard in Typo's product.

BlackBerry is seeking numerous rulings, including damages from Typo, all of Typo's profits and a stop to future sales of the keyboard technology.

"We are flattered by the desire to graft our keyboard onto other smartphones, but we will not tolerate such activity without fair compensation for using our intellectual property and our technological innovations," Blackberry chief legal officer Steve Zipperstein said in a release.

BlackBerry has been fighting a losing battle for market share against its touchscreen competitors, which include Apple Inc. and phones on the Android operating system. However, its keyboard model has remained popular with many users.

A year ago, the company attempted to enter the touchscreen race with gusto by launching the BlackBerry Z10, a device that turned out to be a sales flop.

The company has been trying to turn around its operations with a new CEO after posting a $4.4-billion loss in the most recent quarter.

On Friday, BlackBerry shares closed down 12 cents at $8.09 on the Toronto Stock Exchange.