ok...I'll stick my nose in here (and probably get it chewed off
I do appreciate your concern Lauryn, and applaud your desire to do something. I know this thread is a bit old, but there has been some misinformation in some of the responses here and the most important aspect of this has gone unmentioned. I would like to fill in a couple gaps if I may.
First, you do not need to prove ownership of copyright to file a DMCA. As a career artist and photographer I have filed several over the years. All you need is a sworn statement that you hold the rights. The 'offending' party will not get in trouble. By law, the ISP (LL in this case) must remove the contested work and inform the person posting it the reason for the removal. They can then submit a counter claim to have the work reinstated. The ISP then gives both parties the contact info of the other so they can settle it between themselves. As long as the ISP complies with the law they are a disinterested party. If they do take an interest either way it can drag them into a legal action. So it will be rare for any ISP to take any action other than to remove or restore items at the request of claimants. That is not by their own choice. The law itself restricts their actions. It is not their place to judge the legitimacy of copyright claims. That must be left to the courts. And this is why they cannot take action on the word of another disinterested party.
As far as proof in court, everything now is automatically copyrighted by the creator at the moment of conception. All you need to do is prove you created it to win a case and that is VERY easy with most digital art. When all the infringer has is a 600 x 800 JPG and the artist has a 4000 x 4000 pixel PSD, or even better an EPS, with the layers separated out as well as all original source files...case closed. If I post a really good photograph keep in mind that I probably have a series of pictures of the same subject and setting that could include hundreds of shots in my camera's raw format. I could easily prove copyright of any of my pictures in court. Also, most of my professional work is represented by large agencies with staff attorneys. But that is generally not wall art like I sell in SL.
SL is overflowing with obviously copyrighted works. I just saw a legitimate store selling 4 Beatles songs for 200L$. It is rare that I can walk into a store in SL and NOT see copyright infringement somewhere. It is even common in the in-world offices of Lindens. This is not malicious but simply lack of thought or understanding. With the new mesh you have to pass a copyright test before you can upload meshes, but one prominent Linden recently displayed a copyright infringing avatar as a great example of what you can do with mesh. This particular Linden also mentioned he failed the copyright test the first time. But look through the gestures in your own inventory and ask yourself about any sound files attached to them. It is a cultural thing that involves almost everyone, often even those who protest the loudest against it.
Many second life "artists" just grab pictures from anywhere on the web, slap a few photoshop or gimp filters on them and call them their own art. Or they "photograph" someone else's 3D art builds in SL, slap a grunge filter and frame on it (usually a frame picture from some frame site on the web), and call it their own art. Almost all of this is copyright infringement. (copyright includes rights to all derivative works). Even if it isn't copyright infringement it is artistic plagiarism at best. You can't just frame a Renoir and call it your own art.
Yes, this is stealing from the original artist but that is not the biggest issue here. Think about this...as an artist I must compete, using only my own skills, against the best work of the greatest artists in the world selling for pennies. I'm good...but not THAT good. No one is. I saw a gallery last week full of Thomas Kinkade paintings selling cheaper than I sell my art. Think about your own RL career and how you would feel if that was somehow done there, forcing you to work for pennies per day or do something else. If all artists chose to do something else... We certainly won't see any legitimate Kinkade works in here as long as this is going on. It isn't worth the time and effort. And that is a serious loss to SL.
If all the infringing work was removed from SL I would be making at least 10 times what I am making in here now. This is an issue facing nearly every artist in the world today and not just in SL. Even the likes of Thomas Kinkade cannot effectively compete with the very best images of the very best artists around the world being sold for pennies on the dollar. I ran into the same thing in web design when ALL my competitors just grabbed Vargas pinups when they needed an image like that. I had to either create something myself or pay heavy license fees to compete with that quality of work. When they did come to me for contract art it was often a request to edit a copyrighted work to better fit their site. (which I always refuse).
So ALL artists have a real loss of income here. But it is more a matter of general culture and education than a few people being bad guys. I can find offending works in pretty much anyone's inventory. That is the real problem. I appreciate the new policies Linden has for meshes. All they need to do is learn them and start following them themselves...like a certain semi official building tutorial supported by LL that uses a certain Mad Magazine character to advertize. They licensed that, right? When I need a comic character I have to create an original one. And if they were playing fair they would have to come to an artist like myself to have one created. So even that seemingly harmless use is hurting real artists.
You get what you pay for. If you pay artists you get more art. If you pay thieves you get more theft. It's a choice we all make together.