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However, Blizzard Entertainment Inc. grants "a personal, non-exclusive, non-transferable and non- assignable license to use and display, for home, noncommercial and personal use only, one copy of any material and/or software that you may download from [their] site, including, but not limited to, any files, codes, audio or images incorporated in or generated by the software (collectively the "Downloaded Content") provided, however, that you must include or maintain all copyright and other notices contained or associated with such Downloaded Content."
The use of files in question is also believed to qualify as fair use under United States copyright law, as such display does not significantly impede the right of the copyright holder to sell the copyrighted material.