The verdict, by a jury in the US District Court for the Southern District of California, found that the iPhone 7, 7 Plus, 8, 8 Plus and X infringed two patents, and the iPhone 8, 8 Plus and X infringe a third.
The three patents in question cover technologies that were invented by Qualcomm in San Diego, a statement from the company said.
One of the patents covers technology that enables flashless booting; it eliminates the cost and footprint of separate flash memory and allows a smartphone to connect to the Internet quickly after being powered on.
A second patent covers tech that enables smartphone apps to send and receive data to and from the Internet by acting as a smart "traffic cop" between the processor and the modem.
And a third is for tech that makes high performance and rich visual graphics possible for games, while increasing the battery life of a smartphone. All three patents are not essential for any mobile standard.
“Today’s unanimous jury verdict is the latest victory in our worldwide patent litigation directed at holding Apple accountable for using our valuable technologies without paying for them,” said Qualcomm executive vice-president and general counsel Don Rosenberg.
“The technologies invented by Qualcomm and others are what made it possible for Apple to enter the market and become so successful so quickly.
"The three patents found to be infringed in this case represent just a small fraction of Qualcomm’s valuable portfolio of tens of thousands of patents. We are gratified that courts all over the world are rejecting Apple’s strategy of refusing to pay for the use of our IP.”
Apple has not made any publicly available statement about the outcome of the trial.