Ok, both of these comments made me doubt my memory so I just checked and my current employer, a very large consumer company, and the limits of the program are that you get a C or above, and the class is "related" to your job or any job you can get at the company. But I've gotten classes paid for that only tangentially related to my job with no problem. So I concede that you might not get a biology degree as an engineer but my particular company does a lot of different things so my guess is in practice you'd have no problems. I also worked at a now-defunct mid-size startup and a hospital system with similarly loose requirements but I don't have access to their docs anymore.