ST. LOUIS - A Missouri federal judge on Dec. 31 granted certification to a class of pizza delivery drivers alleging various minimum wage violations and denied their employers' motion to strike the report and testimony of the plaintiffs' expert witness (William Timothy Perrin, et al. v. Papa John's International, Inc., et al., No. 09-1335, E.D. Mo.; 2013 U.S. Dist. LEXIS 181749).