The company I work for received a large amount of negative feedback for imperfections in a lot of the products they produce. Instead of replacing the outdated, damaged equipment responsible, I spent weeks refurbishing the existing equipment, bringing them back to life, as good as new, saving the company tens of thousands, if not hundreds of thousands of pounds. This guy took the whole credit despite his entire contribution being asking me if there's anything I can do about it, and at the end of the project confirming it was successful (he works in quality control, I'm an engineer).