https://techcrunch.com/2019/01/15/how-do-you-fight-an-algorithm-you-cannot-see/

That question in the headline was the challenge posed by a group of open knowledge junkies in Germany who wanted to understand how a person’s Schufa was calculated. Schufa is a credit bureau that generates financial scores for potential borrowers in Germany, and it is roughly equivalent to a FICO score in the United States. Schufa is not an open algorithm, and so important financial decisions are mediated by an unknown process that can be quite capricious in its scoring.

So the activists created a platform called OpenSchufa that would attempt to discover the details of this algorithm. Under German law, citizens have the right to request their financial data from companies like Schufa, and so a movement was created to get as many citizens to request their data from the company as possible and then have them donate the data they receive to the project.