CFIUS reviews M&A deals for any potential national security issues. During the proceeding it needs to balance the legal right of capital to freely enter and dep

CFIUS reviews M&A deals for any potential national security issues. During the proceeding it needs to balance the legal right of capital to freely enter and depart the country with maintaining secure supplies and critical know-how. For all we know, Lumileds may be a key supplier for a tier one DOD project, their know how may be exploited to infiltrate US military systems, or foreign ownership may potentially reduce strategic strengths of the US economy in the event of a conflict with the owner's native jurisdiction. (These are possible reasons, I don't know anything specific about Lumileds operations) Since we don't know why they actually got the deal denied, the best we can do is speculate. Because the deal concerns assets located in the US, CFIUS gets automatic jurisdiction on the transfer of those assets. As for the legality of blocking the transfer on national security grounds, our laws leave open many loopholes for the government to use.