After one day of sending my CV, I got the call for an interview from the hiring manager. The interview was pretty straightforward and later I was asked to complete a case study. Even though baldy worded; the case was extremely easy and I was requested to complete it in iPython preferably. I decided to use a distribution package instead, judging from the lack of quantitative modelling knowledge as well as language processing skills of the employees in most of the startups; I wanted to put them to task. After submitting the test, the hiring manger informed me that he is waiting on the data analyst team to review the code. As python is not backwards compatible and has significant changes in code when run on ipython console or in a distribution package, I had a strong inclination that their 'data' team will be too incompetent to decipher something so simplistic. Either that or as others mentioned here, they are only using free labour to garner unethically tapped creativity for their own gains. This is absolutely illegal in Germany and therefore everyone is advised not to send their written codes to any company. They can only request an output but not your work. And if such case does arise and they have used your work, please by all means sue them. Even a hint of them using your work gives you enough rights to sue. All highly qualified professionals please avoid this company and others alike, and also promulgate the unethical practices so people are not taken unfair advantage of.