None of the patterns below prove that a company is doing anything wrong on their own — plenty of honest, well-run businesses will trigger one or two of these at some point for entirely legitimate reasons. But each is a real, well-documented signal that professional analysts and forensic accountants watch for, and each is worth understanding well enough to investigate further rather than ignore. A persistent, widening gap between reported revenue growth and actual cash flow from operations is one of the most closely watched: if a company keeps reporting rising revenue while the cash actually coming in from operations stays flat or falls, it can point to aggressive revenue recognition or real difficulty collecting on sales already booked.
Other patterns worth knowing: receivables growing meaningfully faster than revenue (customers taking longer to pay, or revenue booked prematurely), inventory building up faster than sales (weakening demand or looming write-downs), frequent auditor changes or shifting accounting policies, heavy and persistent reliance on "adjusted" non-GAAP metrics that exclude real recurring costs, and related-party transactions — deals struck with company insiders or their family members, which can sometimes mask the real economics of a transaction.
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