Sound files, graphic images (including web graphics, photos, logos and other digital art), writings, text, HTML, cascading style sheets, javascripts or any other material that you are given permission to use or display on your web site does not entitle you to claim copyright to the material in question. Permission to use someone else's material does not make you the rightful owner or holder; it just gives you the right to use it under the real owner's conditions. The copyright notice at the bottom of a website only pertains to the content that one has actually created, not to what was created by another and is being used with permission. Owner's terms may vary, but it is always best to include text on the same page where the material on loan is being used to specify who the real owner is, and that it is being used with permission. To an extent, this would protect you as well as the appropriate owner as it would be notifying the public that the material is owned by someone...if you failed to properly protect someone else's work that you are using and it turns out that someone else swiped it due to your misuse or negligence you may be subjecting yourself to a claim. "
Article from whatiscopyright.org