BALTIMORE - Direct purchasers of titanium dioxide alleged parallel conduct and "plus factors" sufficient to proceed with their price-fixing claims against two manufacturers, a federal judge in Maryland ruled Aug. 14 in denying the defendants' motions for summary judgment (In re Titanium Dioxide Antitrust Litigation $(All Actions$), No. 10-0318, D. Md.; 2013 U.S. Dist. LEXIS 114927).