Flip side, I’ve done a couple of these and if it is through an agency then it will all be very carefully controlled, the client will not ask for commercially sensitive information and if it should hit those sorts of areas then you can simply say that it is commercially sensitive and they won’t push.
I did one for example on sunscreen active ingredients; the client wanted a broad overview of the market and -> my opinion <- of whether it was a growth area, potential enviro / regulatory issues for specific types of actives, and so on. No info was requested or discussed about volumes, either market or my company’s, or pricing – they just wanted ‘expert’ opinion on certain aspects, the kind of stuff I’d discuss openly at a conference with competitors, customers and colleagues.