Ironworks Patents, fresh off a nearly $11 million patent win over Apple Inc. this summer, is suing the tech giant again, alleging continued infringement with its later-generation iPhones, including iPhone 8 models and the iPhone X.

In a complaint filed Oct. 6 in Delaware federal court, the Chicago-based nonpracticing entity said it was suing out of an “abundance of caution” to preserve its rights to seek damages on the recent iPhone models.

In July, U.S. District Judge Sue L. Robinson of the District of Delaware awarded the company $8.9 million in enhanced damages, nearly tripling a $3 million jury verdict against Apple for infringing Ironworks' so-called '231 patent with “polite-ignore” features built into iPhone 3 and 4 models.

The damages award represented a 12.5-cent royalty for each of the 71.5 million iPhones that Apple had sold with the infringing technology. Robinson also granted Ironworks almost $2 million in pre and post-judgment interest in the case, bringing the total award to just under $11 million. 

Apple's appeal is currently pending before the U.S. Court of Appeals for the Federal Circuit.

Ironworks' new suit asserts claims on the same patent, alleging infringement with variations of the iPhone 4, 5 and 6 models.

But it also includes two patents for similar technology that were not subject of Robinson's ruling in July. Those patents, allegedly incorporated into iPhone 6, 7 and 8 models and the iPhone X, claim an alert system for incoming calls that can be felt—but not heard—by the user.

“As a direct and proximate result of Apple's acts of patent infringement, Ironworks patents has been and continues to be injured and has sustained, and will continue to sustain, damages,” Ironworks' attorneys Michael Farnan and Brian Farnan, of Farnan LLP, said in the complaint.

Ironworks is again seeking royalties and enhanced damages in the case, as well as interest and attorney fees.

Apple's press shop did not respond Monday to a call requesting comment on the lawsuit.

Robinson had rejected Apple's attempt to overturn the jury verdict in June, saying the Cupertino, California-based company's requests for a new trial and judgment as a matter of law simply rehashed arguments that had already failed at trial and on its earlier motion for summary judgment.

Ironworks, which had inherited the “polite-ignore” patent and the litigation from MobileMedia Ideas, had argued a wide range for royalties and asked Robinson for enhanced damages of up to 83 cents for each infringing iPhone that was sold. The judge, however, settled on the low end of the spectrum, finding that it was the only amount supported by the evidence at trial.

“The 12.5 cents/unit royalty is the lowest damages award supported by sufficient evidence; therefore, the court adjusts the damages award to $8,940,544,” she wrote in a 30-page memorandum opinion.

The patent, which allows users to silence rings from incoming calls without the caller knowing, was the fourth Apple was found to have infringed in the six-year case. In December 2012, another jury in Wilmington found that Apple's iPhones had infringed on three MobileMedia patents for changeable keys and features for rejecting, silencing and merging incoming second calls. Those too are now part of Ironworks' portfolio.

The two new patents, identified in the complaint as the '150 and '734 patents, were initially assigned to Nokia Mobile Phones Ltd., though it wasn't clear from the complaint when Ironworks had acquired them.

The case, captioned Ironworks Patents v. Apple, has not yet been assigned to a judge.

Robinson, who has retired from the district court over the summer, now works with the Farnan law firm in Wilmington. In a letter to the court, Michael Farnan on Oct. 6 said that the firm had implemented a screening procedure to prevent Robinson from participating in the cases or receiving any fees connected to the litigation.

Tom McParland of Delaware Law Weekly can be contacted at 215-557-2485 or at [email protected]. Follow him on Twitter @TMcParlandTLI.