BLACK HILLS ENERGY
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United States Patent and Trademark Office
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37, 39, 40
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2014-07-15
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details
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United States Patent and Trademark Office
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37
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2014-07-01
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details
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BH
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United States Patent and Trademark Office
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36, 39, 40
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2013-08-06
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details
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IMPROVING LIFE WITH ENERGY
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United States Patent and Trademark Office
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36, 39, 40
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2012-04-17
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details
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BLACK HILLS CORPORATION
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United States Patent and Trademark Office
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36, 39, 40
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2012-04-17
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details
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SERVICE GUARD
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United States Patent and Trademark Office
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36, 37
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1993-07-27
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details
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SERVICE GUARD A DIVISION OF AQUILA
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United States Patent and Trademark Office
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36
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2006-06-06
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2013-01-11
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historic |
details
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BLACK HILLS FIBERCOM
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United States Patent and Trademark Office
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38
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2003-01-21
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2009-08-29
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historic |
details
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BLACK HILLS FIBERCOM
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United States Patent and Trademark Office
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38
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2001-03-06
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2007-12-08
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historic |
details
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