Custom Fields Showing Up Everywhere

I’ve created a custom post type for case studies. It contains several custom fields such as first name, last name, company, customer_image_url, etc. The custom post type works fine, but the problem is that the custom fields show up in the standard “Posts” in WordPress.

For example, if I add a new post using the built-in post type, all the custom fields for the other post types will show up after I’ve saved the post. Before I save, it shows the standard drop down menu with all the custom fields from the custom post type, but even if I don’t add any to the post, after saving, they will all show up as blank.

Anyone else experiencing this or have a solution?