Hi @favor i thank you for contributing to the Lucid for Developers Community space. As this issue does not appear to concern our APIs I’ve moved your post to our Lucid Suite Community space. 

If you are editing a document and would like to hide specific data from view you will first want to move the data to its own layer - from there you can turn off visibility of the specific layer our Layers Article from our Help Center has a ton of helpful information specifically regarding layer visibility.

To move the data to a layer I recommend you select all the cells you want to move and copy/paste it in the layer. To hide and lock a layer navigate to the layers button in the bottom right corner of your screen and select the Lock Icon and Eye Icon to lock and remove visibility. This can be toggled on and off as you desire. Click "Sync visibility" to set this as the default for users when they access it. 


​​Once this has been done this is where user permissions and sharing come in. To keep the data hidden if shared with another user the user must be invited as a view only user with no editing permission. With View Only permissions viewers will not know there are hidden layers of data - they can only view what you have made visible. If a user is invited as an editor they will see the layer function in the corner of their screen and can adjust what is visible.