Every official agilent distributor I have seen will only sell at the agilent approved price. However, Agilent's price structure is complicated and flexible: there are a number of discount options available at any given time, demo equipment and so on. It may be that agilent approved a discount because they were behind on stock, or it could be that the distributor signed you up for a discount that you didn't ask for or didn't qualify for. For instance, educational discount is 15% on all agilent products -- that sounds like about the discount you received. I don't know how well agilent polices this sort of thing, but the distributors have a lot of incentive to try to help you. They know you can go to any other agilent distributor or direct from agilent and get an identical product at an identical price, so "do you have stock and can you deliver" are about all they have to compete on.