You should not use copyrighted or trademarked material in Second Life, unless of course you have a right to use the intellectual property. Your rights are defined by applicable copyright and trademark law, including the law of fair use.
Real world laws apply to intellectual property infringement, and nothing about your use of Second Life will shield you if you are infringing on someone else's intellectual property- the rightful owner of the IP can take direct legal action against you in real world courts of law.
The following describes more detail about how Linden staff treat trademark and copyright issues in-world:
Linden staff generally removes content that uses trademarks without apparent authorization, with or without giving notice to the object owner. This generally includes all RL corporate logos and brand names.
It is often difficult to tell what may or may not be trademarked. However, use of designer logos and brand names without permission, such as Gucci, Nike, Louis Vuiton, etc., are usually not acceptable. Any resident may file an abuse report if they see any other resident making unauthorized use of trademarked material in SL.
For more information, visit the US Patent & Trademark Homepage:
You can also use the trademark look-up feature on that website: Use the Search tool under Trademarks on the left navigation when you go to US Patent & Trademark Homepage.
Linden Lab follows the procedures described in the Digital Millennium Copyright Act (DMCA) regarding copyrighted materials. This generally means that Lindens will not remove copyrighted material unless the owner of the copyrighted material notifies Linden Lab in accordance with the DMCA process noted on their website, at:
If a DMCA notice is filed, and it meets the standard for a complete claim, Linden Lab will then expeditiously remove the indicated materials in-world. Note that the item must appear in-world for Linden Lab to take any action.
Repeated copyright or trademark violations by a resident can result in their account being placed on probation or permanently banned.