Antitrust suit against producer of raw metal cannot relate back its revised claim, making it untimely; the shift from industrial plaintiffs to the end users of the products gave the defendants insufficient notice to preserve documents and prepare for trial.
State antitrust laws likely require closer proximancy than the end user of the products, as loss calculation becomes difficult.
http://media.ca7.uscourts.gov/cgi-bin/rssExec.pl?Submit=Display&Path=Y2018/D09-06/C:17-2910:J:Wood:aut:T:fnOp:N:2213421:S:0
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.