The Metropolitan Council, which oversees the Central Corridor light-rail project, began hearing complaints about the J-MOS firm nearly a decade ago.

2002: Contractors on the Hiawatha light-rail and waste water treatment projects complain that the firm made misleading statements about the materials it could supply.

2007: The Met Council detects "several areas of concern" about the firm's inventory.

2009: The Met Council concludes that the inventory was proper.

March 2011: The Met Council admonishes the firm about alleged improprieties.

July 2011: The Met Council disqualifies the firm from participation in the minority business program.

Source: Findings of an inquiry by the Metropolitan Council, the Metropolitan Airports Commission and the Minnesota Department of Transportation.