Once you’ve got a case study you’re happy with, email the PDF to the customer for his or her approval. Wouldn’t it be easier to send them the non-PDF file so the customer can make changes? Yes, but that’s exactly what you want to avoid. A PDF file seems hard to change, and in many cases it will discourage customers from making line edits (adding or removing commas, for example). If they really feel strongly about changing something, they can tell you and you can make the edits. This will not only help you do a better job keeping track of different versions, but also help you control the overall message of the case study.
That said, never argue with a customer. If he or she wants to remove a key metric, take it out. Find something else to swap in, or just live with it. There will be other opportunities, and a case study is not worth annoying or angering a customer.
In your email, be sure to remind the customer where the case study will be used once they approve it—your blog, website, a press release, Twitter, etc. Remember that one of the main reasons customers agree to participate in case studies is free publicity for their own companies.
Advanced Topics in Approvals: Legal Release Forms
Getting a verbal okay from a customer that a case study is ready to go is good; getting an approval in an email is even better, since you’ll have a record you can pull up later in the rare case any disputes arise (this assumes, of course, that you don’t delete your old emails). If you have a legal department or advisor, they will probably insist that a release form is the best way to ensure that both you and your customers are on the same page about case study content, approvals, future use, and other parameters.
Out in the corporate wilds, I’ve seen it work both ways. I would say only about half of the companies I wrote for used case study release forms, and even then the marketing teams weren’t especially diligent about making sure the forms were filled out, collected, and filed. Whether you use a form or not is ultimately up to you. If your customers are bigger, better known companies, using a release form is wise; they’ve probably seen similar agreements many times before and will have no problem passing it off to their legal departments for review. If you work with smaller companies, bringing out the legalese might spook some of them and make them less likely to agree to a case study. In these cases, an email will probably be fine.