The Chief Justice assigns circuit judges to sit by designation with another circuit or district court pursuant to 28 U.S.C. § 291.
Since 2006, judges on the Federal Circuit have sat by designation on another circuit or district court 85 times [1].
The numbers of Federal Circuit judges sitting by designation with another circuit or district court are as follows:
2019: 4
2018: 4
2017: 8
2016: 4
2015: 4
2014: 7
2013: 2
2012: 3
2011 :3
2010: 10
2009: 8
2008: 8
2007: 5
2006: 6

