Judge Kimberly Moore was sceptical that Apple was being harmed since it already licenses some technology to other companies. "You've already licensed these patents up the wazoo!" she said.
In three years of gloves-off patent litigation, Apple and Samsung have battled to a virtual draw. The sole exception was when jurors awarded the iPhone maker about $930 million after a 2012 trial. Samsung is appealing that judgement.
In the latest round, Apple is seeking an injunction against sales of some Samsung products it says infringe on its patents for technologies such as slide-to-unlock, auto-correct and quick links that can, for instance, send a telephone number from an email to the phone dialer.
Apple lawyer William Lee of Wilmer Cutler Pickering Hall & Dorr LLP said Samsung could quickly design work-arounds for the patents but did not do so. He told the U.S. Court of Appeals for the Federal Circuit in Washington that Samsung was harming Apple.
Moore disagreed: "You've licensed them to everyone. So why is it irreparable harm if Samsung uses the patents?"
Judge Sharon Prost said she was "having a hard time getting past irreparable harm."
Samsung lawyer Kathleen Sullivan of Quinn Emanuel Urquhart & Sullivan LLP said the South Korean company had all but stopped using the patents, so no injunction was needed.
"Why are you fighting it?" said Moore. "Why am I wasting my time?"
Some industry observers see the dispute as an attempt by Apple to curtail the rapid growth of phones based on Google's rival Android software. Samsung was by far the largest adopter of the operating platform.
The case in U.S. District Court, Northern District of California is Apple Inc vs. Samsung Electronics Co Ltd, 12-630.
The case at the U.S. Court of Appeals for the Federal Circuit is Apple Inc v Samsung Electronics, 14-1802.
© Thomson Reuters 2015