A few years before Apple introduced the iPhone, research engineers at Nokia prepared a prototype of an Internet-ready, touch-screen handset with a large display, which they thought could give the company a powerful advantage in the fast-growing smartphone market.

The prototype was demonstrated to business customers at Nokia’s headquarters in Finland as an example of what was in the company’s pipeline, according to a former employee who made the 2004 presentation in Espoo.

But management worried that the product could be a costly flop, said the former employee, Ari Hakkarainen, a manager responsible for marketing on the development team for the Nokia Series 60, then the company’s premium line of smartphones. Nokia did not pursue development, he said.

“It was very early days, and no one really knew anything about the touch screen’s potential,” Mr. Hakkarainen explained. “And it was an expensive device to produce, so there was more risk involved for Nokia. So management did the usual. They killed it.”