BlackBerry, the troubled Canadian company whose stock fell 37 percent last year and that wrote off $1 billion in unsold inventory, is going on the offensive.

The firm is suing "American Idol" host Ryan Seacrest — or more specifically, the startup that he launched — over an attempt to make a physical keyboard adapter for iPhones.

The problem, according to BlackBerry, is that Typo's keyboard looks suspiciously much like BlackBerry's own design.

"This is a blatant infringement against BlackBerry’s iconic keyboard, and we will vigorously protect our intellectual property against any company that attempts to copy our unique design," said Steve Zipperstein, BlackBerry’s top lawyer, in a statement. "We are flattered by the desire to graft our keyboard onto other smartphones, but we will not tolerate such activity without fair compensation."

BlackBerry's suit comes days after the company parted ways with another high-profile figure, singer Alicia Keys. Keys had served for the past year as the company's creative director.

In fairness to BlackBerry, Typo's product does look rather similar. But stomping on a potential threat that happens to meet the needs of those who want a physical keyboard and a stylish, functional device in one package could end up backfiring.