Some storied rivalries never die. In the case of Steve Jobs and Bill Gates, that rivalry lasted their entire professional lives and tied the two men together in a relationship that was at times fractious but still symbiotic. During an interview with ABC News, Gates summed up his professional rivalry with Jobs as sometime co-workers who spurred each other on.

The interview with "This Week" anchor Christiane Amanpour covered Gates' philanthropy and his lobbying in Washington but the part that caught the interest of most of the tech world was his response to Jobs' criticism of him in Jobs' new biography. In the biography "Steve Jobs," author Walter Isaacson quotes Jobs saying of Gates:

"Bill is basically unimaginative and has never invented anything, which is why I think he's more comfortable now in philanthropy than technology. He just shamelessly ripped off other people's ideas."

Gates was unperturbed about the comments.

"None of that bothers me at all," he told Amanpour.

"Steve Jobs did a fantastic job."

Gates reflected on the work he did for Jobs' first Macintosh computer and how he had more Microsoft people working on the project for Apple.

"Over the course of the 30 years we worked together, you know, he said a lot of very nice things about me and he said a lot of tough things," Gates said.

"We got to work together. We spurred each other on, even as competitors."

Gates was his usual mild-mannered self during the interview but even then a hint of competitiveness came through when he talked about Apple's business plan that targeted only high-end consumers.

"He faced, several times at Apple, the fact that their products were so premium-priced that they literally might not stay in the marketplace," Gates said.

"So the fact that we were succeeding with high-volume products, you know, including a range of prices, because of the way we worked with multiple companies, it's tough."

"And so the fact that ... at various times, he felt beleaguered, he felt like he was the good guy and we were the bad guys, you know, very understandable," Gates added.