This complaint runs around the internet like the proverbial chicken with its head cut off. But it’s worth noting what can be stolen and what cannot as well as what can be copyrighted and what cannot.
Facts cannot be copyrighted. I may spend a small fortune to discover that Johann George Trautvetter who was born in 1798 in Bad Salzungen, Germany, was the son of Erasmus Trautvetter. I can’t copyright that fact. If I write a five paragraph proof argument to establish it, those five paragraphs are subject to my copyright. The fact that Johann George was the son of Erasmus is not something I can copyright.
I can spend a slighter larger fortune documenting the children and grandchildren of Erasmus Trautvetter and then put that information on the internet. Those relationships, dates of birth, death, and marriage, are not copyrightable. They are not “my” information. Others can use it and not cite me, not give me credit, ask my permission, kiss my feet, etc. A lengthy narrative about Erasmus’ descendants with extra information and a dose of my literary whit? That is copyrightable and is “mine.” The general family structure is not.
If you are going to be outraged because someone uses “your” information without crediting you, there is one way to prevent that from happening completely:
don’t put it on the internet.
Remember: specific facts are different than longer written narratives. Those narratives are copyrighted. How practical it is to initiate a copyright infringement lawsuit is another matter entirely.
How you feel about someone “using” what you’ve put online is up to you. Just don’t be surprised if it happens.