A foreign investment requires a mandatory CFIUS declaration only if it is a covered transaction and meets one of the applicable mandatory-filing tests. The two principal routes concern certain investments involving critical technologies and certain acquisitions of a TID U.S. business where a foreign government has a substantial interest in the foreign investor. A transaction that does not meet either test may still fall within CFIUS jurisdiction.
Start by asking whether the transaction is covered
Foreign participation alone does not make a deal subject to mandatory filing. First determine whether the transaction is a covered control transaction or a covered non-controlling investment under 31 C.F.R. part 800. Those terms have regulatory definitions and exclusions; not every foreign share purchase qualifies. Certain real-estate transactions are addressed separately under part 802.
As an Amazon Associate I earn from qualifying purchases.
For an investment covered by part 800, screen both mandatory routes below. The outcome depends on the transaction, the U.S. business, the investor and its ownership chain, and any applicable exceptions—not nationality or a single ownership percentage in isolation.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Scan for outdated or missing drivers - takes under a minute3Clear out junk files and repair common Windows errorsCompare the two principal mandatory-filing routes
| Question | Critical-technology route | Foreign-government/TID route |
|---|---|---|
| What is acquired? | A covered transaction involving a U.S. business that produces, designs, tests, manufactures, fabricates, or develops a critical technology. | A foreign person acquires a substantial interest in a TID U.S. business. |
| What additional test applies? | A hypothetical transfer of the relevant technology to the direct acquirer or a relevant owner would require a specified U.S. regulatory authorization. | A foreign government has a substantial interest in the foreign person acquiring the U.S. business interest. |
| What ownership detail matters? | The authorization analysis includes a person with 25 percent or more voting interest, directly or indirectly, in the direct acquirer; in certain circumstances it also reaches the acquirer’s general-partner ownership chain. | Direct and indirect interests can matter. The detailed calculation depends on the regulation and ownership structure, including relevant entity and investment-fund rules. |
| What could change the result? | Whether the item is a CFIUS critical technology, whether a specified authorization would be required, and whether a license exception or other regulatory carve-out applies. | Whether the business and investment meet the defined TID and substantial-interest tests, and whether an exception applies. |
The table is a screening aid, not a substitute for applying the full definitions and exceptions in the current regulation to the transaction documents and ownership chart.
#1 Best Overall
Apply the critical-technology test
Confirm the business develops a defined critical technology
A company’s presence in a technology sector is not enough. Determine whether the U.S. business produces, designs, tests, manufactures, fabricates, or develops a technology that qualifies as a “critical technology” under the CFIUS rules.
Do not treat inclusion on the Commerce Control List as conclusive. Treasury’s FAQ explains that some listed items are not “critical technologies” for CFIUS purposes; the CFIUS definition must be assessed separately.
Rank #2
Test the hypothetical transfer and relevant parties
For qualifying technology, ask whether a hypothetical export, reexport, in-country transfer, or retransfer to the direct acquirer—or to a person with 25 percent or more voting interest, directly or indirectly, in that acquirer—would require a specified U.S. regulatory authorization. In certain circumstances, the inquiry extends up the acquirer’s general-partner ownership chain.
Some license exceptions provide carve-outs. Because the result can turn on the technology, destination, recipient, ownership chain, and applicable export-control rules, a broad label such as “foreign investor” or “U.S. tech company” cannot settle the test.
Rank #3
Apply the foreign-government and TID test
The other principal route concerns a covered transaction in which a foreign person acquires a substantial interest in a TID U.S. business, while a foreign government has a substantial interest in that foreign person. TID refers to businesses involving critical technologies, covered investment critical infrastructure, or sensitive personal data.
“Substantial interest” is a defined regulatory term, not a shorthand for any foreign-government connection. Indirect interests and specific rules for entities and investment funds can affect the calculation. Use the current part 800 text and the full ownership chart rather than relying on a simplified percentage or a single direct shareholder.
Check exceptions and investor status
Review applicable exceptions only after identifying the transaction and testing the relevant mandatory route. Treasury says certain transactions involving excepted investors may be exempt from mandatory filing, but excepted-investor status does not remove CFIUS authority over control transactions. Confirm both the investor’s status and the precise scope of any exception under the current rules.
Set the filing deadline using the earliest transfer date
A mandatory declaration must be filed at least 30 days before expected completion. Treasury’s FAQ describes completion as the earliest date on which any ownership interest is conveyed, assigned, delivered, or otherwise transferred. If equity transfers before related control or covered-investment rights vest, that earlier equity transfer may set the completion date and the filing calendar.
Best Value
- Map every planned transfer of equity, ownership, and relevant rights, including staged or split closings.
- Identify the earliest date any ownership interest is expected to transfer.
- Schedule the mandatory declaration at least 30 days before the expected completion date, and build the deal timeline around that date.
Parties may file a written notice instead of a declaration. Treasury states that CFIUS has 30 days to act on a declaration; possible outcomes include concluding action, indicating that it cannot conclude action on the declaration and that the parties may file a written notice, requesting a notice, or initiating unilateral review.
Understand what a no-filing conclusion does—and does not—mean
If neither mandatory route applies, the transaction is not thereby cleared or necessarily outside CFIUS jurisdiction. The parties can consider a voluntary declaration or notice, and Treasury says CFIUS may review a pending or completed transaction without a voluntary filing when a Committee member has reason to believe the transaction is within its jurisdiction and national-security concerns may arise.
Treasury’s 2020 critical-technology fact sheet describes a civil monetary penalty of up to the transaction value for failure to file a required mandatory declaration. That is the maximum described in that fact sheet; check the current regulation and penalty provisions before applying the figure to a live transaction.
Recommended Free Tools
What the reported filing figures show
Treasury’s 2025 report on 2024 CFIUS activity says that 116 declarations were assessed in 2024, of which 36 were identified as subject to mandatory filing requirements based on party stipulations. These are figures for that reporting year and those assessed declarations; they are not a count of all foreign investments, a forecast, or a probability estimate for a particular deal.
When to get transaction-specific advice
Use qualified CFIUS counsel for a live deal where the result depends on indirect ownership, investment-fund or general-partner structures, export-control authorizations, an exception, or multiple transfer dates. Check the current text of 31 C.F.R. part 800 and the transaction’s actual technology and ownership records; the screening steps here do not reproduce every definition, exclusion, calculation, or exception.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
