US Market Entry
A tax treaty binds the United States. It does not bind the states.
A foreign company entering the United States takes international tax advice, concludes that its activities fall short of a permanent establishment, and reasonably believes the position is protected. It is protected federally. The states are not parties to the treaty and are not bound by it.
The consequences follow quickly. Permanent establishment analysis does not govern state nexus, and a company with no federal filing obligation can carry filing obligations in a dozen states. Economic nexus thresholds are met by sales volume alone, with no physical presence required. Public Law 86-272 shields far less than its reputation suggests: it reaches only the solicitation of orders for tangible personal property, only for net income taxes, and it does nothing for gross receipts taxes, franchise taxes measured other than by income, or sales and use tax collection. Marketplace facilitator rules can shift collection responsibility without notice to the seller. And a foreign parent that never expected to file anywhere can find its structure drawn into a combined report.
The work is establishing where obligations actually exist before they compound, registering where registration is required, and structuring the entry so that the state position is defensible rather than accidental.