"It was very much like a dorm. People were there all the time," Forstall said. A sign at the entrance said, "Fight Club," because the Purple Building borrowed its cardinal rule from the movie of the same name, he said. The first rule of the movie's Fight Club was to never talk about the Fight Club.

But both Apple executives emphasized the risks the company took by building and introducing the iPhone and iPad. The company hopes to paint Samsung as ripping off Apple's big investments in the products. Apple postponed other products in order to build the team that would develop the iPhone, with no guarantee that the product would succeed, Forstall said.

After Samsung cross examined Forstall about whether Apple had borrowed ideas from Samsung, Apple's legal team asked him whether he had copied that company's phones.

"I never directed anyone to go and copy anything from Samsung," Forstall said. "We wanted to build something great ... and so there was no reason to look at something they'd done."

Apple attorney Bill Lee questioned Samsung's Denison about what it called internal Samsung analyses of the iPhone. One such analysis included the recommendation, "Remove a feeling that iPhone's menu icons are copied by differentiating designs."