I studied in the Netherlands as Czech Erasmus student about 12 years ago and I recall that one had to fill out a questionnaire about their experience and study

I studied in the Netherlands as Czech Erasmus student about 12 years ago and I recall that one had to fill out a questionnaire about their experience and study during the exchange, and that the results were public for anyone to see[1], which included information about home and receiving institution, courses and so on. And people often consulted this database before submitting an application for their stay, so I would not say that they didn't know about it. And while it's likely that local legal conditions differs a bit and that it changed over time, I'm not surprised that such high level data are public. [1] https://erasmus-databaze.naep.cz/modules/erasmus/ https://erasmus-databaze.naep.cz/modules/erasmus/