Customs actually won both the original case[1] and subsequent appeal[2], which leads me to suspect that the underlying motive is less punitive, more intern busy work (annual reviews aside, revision history aligns well with ASME B18.2.1 publication and its errata[3])...or maybe they've somehow justified the effort as "amortizing" legal fees?

[1] http://www.cit.uscourts.gov/SlipOpinions/Slip_op00/00-112.pd... [2] http://caselaw.findlaw.com/us-federal-circuit/1332533.html [3] https://www.document-center.com/standards/show/ASME-B18.2.1/...