Oh hooray copyright. My favorite kind of law. NOT.
Here are a few important facts to remember;
1) You don't have to register for a copy right. The second a work is completed, it is covered by copyright.
2) 'Fair use' considers four factors
(1) purpose and character of use ie commercial, or non-profit educational
(2) nature of work
(3) amount and substantiality and portion of work as a whole ( how much of the work was copied)
(4) effect of use on potential market for work ( is it taking profit away from copyright holder)
Basically, it all comes down to money.
If someone takes your work and sells it without your permission, regardless of whether you are selling it yourself ( note " potential' market) you have a case.
Here's one I hear a lot " Someone took art that I was not selling off of my DA and posted it in their photo bucket BAAAW" Sorry, no case. STFU.
Another little detail here is public access. You especially have no case if they are not making it widely available to the public. ( via private account)
As far as the 'portion 'issue' the work has to be copied in its entirety. You can't claim someone stole a pose, or background. Because, face i, it is impossible to do soemthing 100% original these days.
Also keep in mind, that there are always finite little details to copyrights. So while these are geenral rules, most copyright disputes are settled on a case by case basis.
What about this situation
there was a vendor selling neclaces that you could buy at dollar tree only it was attached to a card board base that had a pic of a japanese singer, said it was their brand of necklaces
thing that tipped me off was the picture, when i looked at the back i could see it was printed by home printer or when you get pics developed at wall greens
there ARE jewlary lines run by japanese singers, but the boths stuff wasnt it, is that allowed?
I'd hate to see some j-rock junkie buying a necklace because they think (enter japanese singer) company made it, only to walk into a dollor tree and see the same thing they paid 20 bucks for
Copryright right only applies to intangible property. Trademarks, are for things liek logos, and patents are for inventions.
They COULD attempt to apply for a patent, but they would most likely fail because well, their beaded necklaces.
All they could do is go afetrt hem for trademark, and that's only IF They copied the companies logo or brand name. Even then they would have to prove that they are losing money/business. Which I highly doubt, in the end, it would hardly be worth their time.