The CEO of Broadcom is a dual British-American national, but not a dual citizen
Tan Hock-Eng is a British national (not a joke)
Because he was born in Penang before August 31, 1957 (independence or Merdeka Day) he was a Citizen of the United Kingdom and Colonies at birth
Additionally the Federation of Malaysia Independence Act, 1957 did not strip Citizenship of the UK and Colonies from those connected to Penang and Malacca. However the Commonwealth Immigrants Act, 1968 and Immigration Act, 1971 ended the possibility for such CUKC to move to the UK unless they had parents or grandparents born in the UK, or they happened to register naturalize, or if they had already settled in the UK to have “right of abode” in the UK
The British Nationality Act, 1981 then reclassified such CUKC as British overseas citizens (BOCs), who are Commonwealth citizens and British nationals, but not British citizens. They can hold British passports and vote in the UK if they live there on a visa, but not move there without a visa.
Now Malaysia (his former country) bans acquiring a foreign passport under Article 24 and considers it enough for losing Malaysian citizenship, but if you never acquire it, youre legally safe. Holding an unexercised citizenship is fine. He is however an American citizen and has been since 1990 (a country that does not ban dual citizenship in any case) so he’s free to apply for one now.
Obviously he could renounce BOC but since America doesn’t require renunciation of previous citizenships, and because renunciation of a largely useless nationality makes no sense, I don’t think he did.