So you decided to go through with this? That's great! 

Before we continue with some practical stuff you'll have to know more about the way we handle collections. No matter what you institution is savegarding or showcasing, chances are that your data consists of objects and something we call metadata. Metadata are the descriptive tags you add to the objects in your database to provide them with context and improve searchability. Metadata can inlcude any kind of describing data like dates, names of authors, geographical information, etc. 

For opening up your collections, we make the distinction between objects and metadata because they generally have a different set of rights attached to them. In most cases, the objects in your collection will be created by others. This means that copyright to these works does not belong to your institution, but to a large number of different authors. This can make it quite hard to make these objects available as open data. If you don't the intellectual property rights to a work, you'll have to ask permission of those who do before you can make it public in a new way.

For metadata however this will seldom be the case. The metadata will mostly be created by your own institution and it isn't even always clear if metadata is subject to copyright or not. To establish copyright, there is some sort of personal input from the creator required. When we are talking about factual data like dates, names, etc., the general rule is that they aren't copyrightable. When the metadata includes more elaborate descriptions that transcend facuality, copyright could be involved but when you wrote the descriptions yourself, you own the copyright and it's up to you