I have a model that has 8 sketches with each sketch being a pattern. After one sketch was made there was another one that needed to be made off of it as a reference. The user went to Tools-- Sketch Tools-- Create Sketch from Entities and basically copied the first sketch to use in a different position on the part. This was done 8 different times to make a total of 16 sketches. They saved the model and closed it out. When they went to open it back up every sketch had lost their sketch plane. They were able to fix the first sketch plane fine but when they went to fix the one they created from entities it does not give the option to edit the sketch plane. So 8 of the sketch planes are able to be fixed and the other 8 when you right click on the sketch the edit sketch plane does not show up. I've never used that option to create a sketch before so I don't know the behavior if the sketch plane is lost. My question is if this is intended behavior or could it be a corrupt file issue. This happens on both our computers.