Private equity and venture capital firms spend months analyzing market dynamics, competitive landscapes, and management teams before writing checks. They stress-test financial models, conduct extensive due diligence, and negotiate protective covenants. But many are underestimating one of the biggest threats to their portfolio returns: regulatory and narrative risk—policy decisions, enforcement shifts, and public backlash that can derail even the strongest business models overnight.AI chipmaker Cerebras Systems filed for its highly anticipated IPO last September, expecting to raise $1 billion at an $8 billion valuation. The company burned through cash for months in regulatory limbo, its national security review frozen due to federal staffing bottlenecks. When Cerebras finally cleared the Committee on Foreign Investment in the United States (CFIUS) review in March 2025, the market had already moved on. But that’s the dirty secret of regulatory delays; they don’t just pause deals, they poison them.Other innovators face something worse than delays: outright prohibition. Multiple urban personal mobility companies achieved unicorn status with near-unprecedented speed, only to see their multibillion-dollar valuations collapse as cities systematically banned or restricted their services. After going public via a special purpose acquisition company (SPAC) in 2021, one major dockless scooter firm was so overwhelmed by municipal regulatory battles across the United States and Europe that it was delisted from the New York Stock Exchange in September 2023 because its market cap fell below $15 million before filing for bankruptcy three months later. Another industry leader suffered a particularly devastating blow when Paris, its most profitable market, banned e-scooters entirely in 2023 following a public referendum. In D.C., local leaders limited company fleet sizes and throttled speeds (and consumer utility) to the pace of the average electric wheelchair.Ticket resale giant StubHub offers another cautionary tale of regulatory risk destroying enterprise value. The company booked $93.9 million in legal and regulatory expenses for 2024, according to its S-1 filing with the Securities and Exchange Commission nearly doubling from $48.2 million in 2023. Multiple state attorneys general have sued StubHub over so-called “drip pricing” tactics, while the D.C. Attorney General filed a separate “bait-and-switch” lawsuit in July 2024. The company’s repeatedly delayed IPO plans, targeting a $16.5 billion valuation, continue to stall as regulatory uncertainty mounts. StubHub’s regulatory tab now accounts for approximately 5% of its annual revenue.But it’s the regulatory whiplash between federal approval and state or local prohibition that has created perhaps the cruelest trap for emerging industries. Lab-grown meat companies spent years and hundreds of millions of dollars securing FDA and USDA clearances before watching a growing chorus of states ban their products entirely. Less than a year after UPSIDE Foods and Good Meat celebrated federal approval in 2023, the state legislatures of Florida and Alabama had criminalized the sale of their products, punishable by a misdemeanor. Drone delivery services similarly invested years and significant resources in securing FAA approvals for beyond-visual-line-of-sight operations before municipalities imposed noise restrictions, flight path limitations, and local bans.Multiple high-flying startups have watched their valuations collapse by 50% or more as regulators scrutinize novel or previously unquestioned business models. Daily fantasy sports operators face constant regulatory uncertainty as states increasingly declare their contests to constitute illegal gambling.Regulatory positioning across virtually all sectors has become a core determinant of valuation, scalability, and exit readiness. Companies that ignore policy risks discover too late that perfect products and strong management teams cannot overcome hostile regulatory environments. Today, the most sophisticated investors conduct regulatory risk assessments before every significant investment, mapping political stakeholders, anticipating policy changes or state policy fragmentation, and building compliance capabilities into their operational improvement plans. They recognize that regulatory positioning can create competitive moats just as effectively as technological innovation or market positioning.Today, the most sophisticated companies build regulatory armor before they need it. In addition to basic regulatory diligence to identify U.S. domestic vulnerabilities, political risk insurance providers offer coverage against foreign government expropriation, regulatory changes, and policy reversals, with limits reaching $150 million and terms extending up to 15 years. Startups should structure operations across multiple jurisdictions to dilute exposure while negotiating regulatory approval conditions into major contracts and funding agreements. Local partnerships offer early insights into shifting political winds, and companies require real-time policy monitoring systems that track legislative activity, enforcement trends, and stakeholder campaigns. Crisis playbooks for regulatory challenges should include pre-identified legal counsel, government relations specialists, and media response protocols. The cost of these hedging strategies pales in comparison to the valuation destruction that follows regulatory blindsides.Too many firms check the regulatory box and move on without identifying real risk. Companies need crisis playbooks for regulatory challenges, just as they maintain plans for operational disruptions or competitive threats. The private capital firms that thrive in this environment will be those that recognize regulatory risk as both a threat and an opportunity. While policy uncertainty can destroy unprepared companies, it can also create barriers to entry that protect well-positioned market leaders. The key is identifying these dynamics before they become apparent to everyone else.The regulatory environment will only grow more complex and unpredictable as geopolitical tensions escalate and domestic political polarization intensifies. But the firms that survive the next decade will be those that finally recognize the billion-dollar regulatory blind spot and begin mapping political landscapes as carefully as competitive ones.The next wave of portfolio disasters won’t come from missed earnings or competitive disruption. They’ll come from policy shifts that transform billion-dollar valuations into cautionary tales overnight. And by then, all the financial models in the world won’t matter because you can’t model what you refuse to see.The opinions expressed in Fortune.com commentary pieces are solely the views of their authors and do not necessarily reflect the opinions and beliefs of Fortune.This story was originally featured on Fortune.com