Recently, as reported on this blog, the U.S. Court of Appeals for the Eighth Circuit emphasized that a party waives its right to arbitration by litigation. And, again, today, the Eighth Circuit has reiterated this straight-forward rule, holding that a defendant’s motion to dismiss a putative class action (without invoking the arbitration clause) resulted in waiver of the right to compel arbitration (notwithstanding an express “reservation” of the right to arbitration).