edit: also this book: http://www.uesp.net/wiki/Lore:2920,_Hearth_Fire
ZeniMax Media, of which http://www.uesp.net/wiki/General:Bethesda_Softworks is a subsidiary, http://fusible.com/2012/05/zenimax-media-files-trademark-for-hearth-fire-computer-game-software/ for "Hearthfire" on May 24, with the information appearing today on the http://tarr.uspto.gov/servlet/tarr?regser=serial&entry=85634522. In the Elder Scrolls universe, there is a month called Hearthfire (September). There is no official word yet as to what they intend to do with the name.
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