Apple said the patent claims of a 70-year-old electrical engineer who maintains he invented the smartphone don’t add up, as the case goes before a jury to decide whether Apple is liable for infringement.

“His invention was using your computer as your cell phone,” Mark Scarsi, Apple’s lawyer, told the jurors in his closing statement today in federal court in Los Angeles. “That’s not an iPhone.”

NetAirus Technologies LLC, a company owned by inventor Richard L. Ditzik, alleged that Apple infringes a patent for a handheld device that combines computer and wireless- communications functions over both a Wi-Fi and a cellular network. Damages he can win in the trial are limited to sales of Apple’s iPhone 4 in the past 13 months.

Scarsi said Ditzik’s initial patent application in 1997 was for a handset that made calls through a laptop computer and that the inventor later changed the patent claims to put e-mail and other functions in the handset rather than in the computer. Scarsi asked the jury to find that the patent was invalid and not infringed by Apple’s iPhone.

Apple “shamelessly” stole Ditzik’s invention, NetAirus’s lawyer, Ray Niro, said in his closing statement.

“Apple somewhere along the line lost their way,” Niro told the jurors. “They lost their sense of responsibility.”

Niro said a royalty of $500,000 would be reasonable for Apple’s use of the patented technology.

NetAirus filed a new complaint against Apple in May, for patent infringement by the iPad, iPhone 4S and iPhone 5, after U.S. District Judge John A. Kronstadt denied the company’s request to amend its complaint and include those models in the case being tried.