I think the schools that produce the most case studies are; HBS by far is #1 and some of them are legends that almost all schools use. Then I forget the order but Ivey, Darden, and Kellogg. I know Kellogg is doing a big push to create more and I was surprised to see numerous Ivey case studies along the way in some classes (they are very good too). Darden is an all case study school so it makes sense the produce a lot too.
I love kellogg cases since they are free and free is always good.
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Kellogg Class of 2010...still active and willing to help. However, I do not do profile reviews, don't offer predictions on chances and am far to busy to review essays, so save the energy of writing me a PM seeking help for these. If I don't respond to a PM that is not one of the previously mentioned trash can destined messages, please don't take it personally I get so many messages I have a hard to responding to most. The more interesting, compelling, or humorous you message the more likely I am to respond.