I heard a rather shocking story recently of a charity who, when they tried to move their data from their incumbent database supplier to a new database they had purchased, were told by their existing supplier that they (the charity) did not actually own the data, the supplier did! And, therefore, the charity would have to pay the supplier in order to have the data!
Unfortunately, when the charity checked with their legal advisors, they confirmed that the contract they had signed with their incumbent supplier did indeed state that the supplier owned the data. In the end, the charity decided that rather than go through what could be a long and costly legal battle, they would pay the supplier what they were asking for.
Although this is very sad, I have to say I don't blame the charity for deciding to do that. I don't know whether such a contract would stand up in court but even if it did not then I am sure that the time, effort and aggravation to get to that point would be awful and the cost could well outweigh the amount the supplier was originally asking for.
I think that what shocked me most about this was that a supplier should even consider saying that they owned an organisation's data, regardless of whether it is a charity. It wouldn't seem fair to me even if it was a commercial organisation who was using the database.
So the moral of this story is to check your contract very carefully when you are buying a new database - or using an ASP/hosted solution - and if in doubt then get legal advice. Don't be left in a position where you don't own your own data!