Qualcomm and Apple on Wednesday wrapped up arguments in a contentious patent infringement trial in San Diego. 

The trial, just the latest skirmish in a long-standing legal feud between the two companies, centers on three Qualcomm technology patents that Qualcomm alleges Apple used without permission on some versions of the iPhone. 

One patent allows a smartphone to quickly connect to the internet once the device is booted up. Another deals with graphics processing and battery life. The third lets apps on your phone download data more easily by directing traffic between the apps processor and the modem.

In closing arguments, Qualcomm zeroed in on the boot-up patent. Apple has argued that its former engineer, Arjuna Siva, co-invented the technology when he was working for the iPhone maker. But Qualcomm counsel David Nelson pointed out on Wednesday that Siva testified he wasn't "claiming to be an inventor." Siva also said he hadn't read the language of the patent.

"What were they trying to hide?" Nelson said in his closing remarks, referring to Apple's defense. "Why not show him those things?"

In Apple's closing remarks, its counsel, Juanita Brooks, opened with a broader argument: that the lawsuit isn't about patents at all. She said the "real motivation" for the complaint is that Qualcomm was upset Apple started to also use Intel chips in iPhones in 2016, after Apple and Qualcomm had previously had an exclusive relationship since 2011.

"This case started when we started using Intel as a second source," she said. "Qualcomm went into a drawer, dusted off some old patents, and threw them against the wall to see if they'd stick." 

She said Qualcomm was supplying chips to the rest of the mobile industry during that time. "We ... should also be able to date somebody else," Brooks said.

In his rebuttal, Nelson denied the claim. "It doesn't have anything to do with that," he said, adding, "We're entitled to get return on our intellectual property."

The patent dispute is just the latest in a wide-ranging legal saga. Two years ago, the Federal Trade Commission, aided by tech companies Apple and Intel, accused Qualcomm of operating a monopoly in modem chips. The FTC argued that Qualcomm's high royalty rates stopped competitors from entering the market, harming consumers. That trial took place in January, and the parties are currently waiting for a decision. The two companies will also meet in court next month, to argue over royalties.

Qualcomm is seeking $31 million in damages, or $1.40 per allegedly infringing iPhone. The damages are for iPhones sold from July 2017, when the lawsuit was filed, that contain chips from Intel. In 2016, Apple started using Intel modems in some models of the iPhone 7 and 7 Plus. Now Intel has replaced Qualcomm in iPhones altogether.

On Wednesday, Nelson argued in closing remarks that Apple didn't object to the damages request because the company didn't make any dispute in testimony. Apple said that's not true. "Let me be clear, we owe Qualcomm not one penny." 

A jury of eight people will now decide on a verdict.

Originally published March 13, 2:01 p.m. PT.
Update, 3:55 p.m. PT: Adds more details from trial.