Union Pacific and Norfolk Southern defended the completeness of their revised merger application in a filing with the Surface Transportation Board, saying it is “comprehensive and complete” while rebutting comments that called for the board to reject the amended application. The UP-NS response filed Tuesday addresses the three areas that caused the board to reject the initial application as incomplete – a lack of market-share data, which they say now uses “the best information available regarding merger-related changes in traffic;” the status of the Terminal Railroad Association of St. Louis, which they say that have “unambiguously and unconditionally” indicated they will not seek to control; and all documents related to the merger agreement. In rejecting the original application as incomplete, the board cited the railroads’ failure to include the complete merger agreement, specifically a section on terms that would allow UP (NYSE: UNP) to walk away from the transaction. That portion of the agreement was included in the revised application filed on April 30. The board has until May 30 to determine whether to accept the revised application or again reject it as incomplete. Recent history shows that a merger application has never been rejected twice. A substantial portion of the UP-NS response – more than 13 of the 46 pages – is devoted to the two railroads’ explanation why they believe they have fulfilled the requirement to provide market-share data, and relies largely on an explanation of the processes their three outside experts used to develop the information in…