It's happened to many websites - they find that the content they have spent time developing is appearing on another site, and often, in a position higher than they received on the Google search results page.
It's actually quite common and it may have even happened to you. Search Engine Roundtable published a post recently about how Google's Gary Illyes responded to the question of why/how this might happen in a panel at SMX East last week and his answer, well, will likely raise a few digital eyebrows.
Illyes indicated that while Google is pretty good at figuring out the original source of content, if a scraped/scraper site is ranking above you, chances are good that there are search quality issues for the original site to address. That's right... it's your fault.
In my experience, scraper sites can rank higher but it is usually only for a short period of time. Those with higher authority in the long term usually win out. That being said, it's always a good idea to let Google know if this is happening to you, and keep a close eye on any messages received through Search Console which may indicate that there is a problem.