It's a standard clause in Germany, and even if it's not in your contract, it's in the law. You even have to notify your employer if you make a discovery related to your job. [1] (patent, technical improvements or similar). As with a lot of laws it's not quite so simple to apply to IT jobs, but for anything that's patent worthy, it's pretty clear.

[1] http://www.gesetze-im-internet.de/arbnerfg/BJNR007560957.htm...

Ah this is another case of people not reading long legal contracts that they sign. I would have been surprised if this wasn't standard in the EU as well as Asia .

Thanks for the hint, I'll have a look at it.

Well, if you're under a german employment contract, you probably should, it could be worth it. It's actually fairly balanced and contains regulation concerning fair compensation etc.