Providing office supplies for commercial businesses could be the final nail in the coffin of the would-be formation of the $6.3 billion StaplesMaxDepot Voltron, with regulators reportedly poised to block the mega-merger next week. The New York Post, citing sources familiar with the matter, reports that regulators continue to have concerns that a union between the office supply chains would result in a single nationwide company serving corporate and government clients. Staples and Office Depot are the largest and second-largest commercial office suppliers respectively, and are truly national distributors, unlike third-place finisher and perennial New York Yankees advertiser W.B.