A company called Corephotonics sued Apple on Monday, alleging that the dual-lens cameras in the iPhone 8 Plus and iPhone X it released last year violate a patent it holds related to a “miniature telephoto lens assembly,” according to Patently Apple, which obtained a copy of the lawsuit. The patent, which was awarded to Corephotonics in January, describes how components inside a telephoto lens come together. The patent is extremely technical and describes air gaps between lens elements.

Corephotonics sued Apple in November for violating four dual-camera patents it holds in its iPhone 7 Plus, the first Apple handset to ship with a dual-lens camera. Although the iPhone 8 Plus was already on store shelves and the iPhone X launched the same month, Corephotonics didn’t include those smartphones in the earlier lawsuit.

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The latest lawsuit against Apple’s iPhone 8 Plus and iPhone X cites those four patents, as well.

In both lawsuits, Corephotonics claims to have attempted to establish a strategic partnership with Apple. But after the companies couldn’t come to an agreement on possible licensing, the lawsuits allege, Apple moved forward without a licensing agreement.

Corephotonics said that it’s owed royalties on the sale of iPhones with dual cameras. The company didn’t say, however, how much it’s seeking in damages.

Apple did not immediately respond to a Fortune request for comment on the lawsuit.