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By Katrina Hamlin

HONG KONG, April 14 (Reuters Breakingviews) - Donald Trump is pausing U.S. tariffs on electronics as his administration prepares an investigation into the whole supply chain and semiconductor sector on national security grounds. That piles pressure on companies from Lenovo 0992.HK to Dell DELL.N to disclose more information on where their goods are made.

Investors are scrambling to keep tabs on Trump’s trade war. On Friday, Washington declared exemptions for items including smartphones and laptops from reciprocal country-based tariffs, including a 145% hit on China which is a big supplier of electronics to the U.S. On Sunday, Trump clarified that he plans to announce the tariff rate for semiconductors over the next week.

Many of the chips brought into the U.S. come packaged into devices; computers alone account for around $100 billion of shipments in 2024, versus just over $80 billion for semiconductors. Deciphering the implications is further complicated by a lack of insight into where products come from.

Take the $13 billion Lenovo, whose shares have fallen some 20% since April 2. The Hong Kong-listed laptop maker, which reported around a third of sales in the Americas in the first half of last year, has more than 30 manufacturing facilities globally, but it does not break down where and in what quantities it produces notebooks and other devices.

That leaves investors and analysts hunting for clues. Last year, the group's ESG report revealed more than 80% of Lenovo's Scope 2 carbon emissions, which cover those from energy used at manufacturing facilities, came from mainland China. That suggests most of its production is in a country Washington dubs an "adversary".

Rivals such as Dell and HP Inc HPQ.N are similarly light on numbers in filings, and outsourcing makes the risks even harder to parse. Such opacity also rules in the fashion and retail industries. Companies hold back from disclosing more because its gives them a competitive edge on costs.

It doesn’t have to be this way. Apple AAPL.O, which airlifted 600 tons of iPhones to the U.S. from India to beat tariffs, states its production is located “primarily” in China and five other countries: Trump also hinted on Sunday that the $3 trillion company could benefit from some tariff flexibility. Automakers including Toyota 7203.T and Hyundai 005380.KS share monthly updates on regional production, breaking down the number of units produced in different locations, or even plants. Pharmaceutical giants such as AstraZeneca AZN.L list key manufacturing bases and lay out where each specific step in the drug-making process takes place. Trump's trade onslaught is ugly but it will force companies to let in a little more light.

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CONTEXT NEWS

U.S. President Donald Trump on April 13 warned that the exclusion of smartphones and computers from his reciprocal tariffs on China could be brief, pledging a national security investigation into the semiconductor sector. That effort could encompass the whole electronics supply chain, Trump said in a social media post.

Trump’s administration granted exclusions from steep reciprocal tariffs to smartphones, computers and some other electronics imported largely from China, according to a notice dated April 11.

Lenovo’s Hong Kong-listed shares fell 24.4% to HK$8.03 between April 2 and April 11.

(Editing by Robyn Mak, Una Galani and Ujjaini Dutta)

((For previous columns by the author, Reuters customers can click on HAMLIN/katrina.hamlin@thomsonreuters.com; Reuters Messaging: katrina.hamlin.thomsonreuters.com@reuters.net))