Patent.
No plain error in Patent Board's refusal to accept new evidence offered solely on the basis of timeliness and relevance. Agency has discretion, not arbitrary/capricious.
Use of a fog machine to test for leaks in a conduit was not particularly obvious.
[Again, we don't know many things, but we especially don't know Patent.]
http://www.cafc.uscourts.gov/sites/default/files/opinions-orders/15-1047.Opinion.12-29-2015.1.PDF
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.