Cirrus Logic Senior Design Engineer interview questions

I was asked to apply for this position by one of their Head Hunters. I had a phone interview with 3 managers. They went through my CV and asked specific questions on my inventions and which design choices I have done to improve the products of my company, which was quite uncomfortable (ever heard of confidentiality?). Working for a competitor of Cirrus, I had to refuse to answer to certain questions or to be vague. They refused to answer to any question specific to their business; even simple things like which technology they use. It gave me the feeling that they were trying to get some insights in the business of a competitor.