Prime Minister Theresa May has said foreign takeover bids for British firms must be assessed to determine whether they're in the national interest.
And the transaction could be the first of many, experts have said.
According to Neil Wilson, markets analyst at ETX Capital, the Arm/SoftBank deal shows "the effect of Brexit and the collapse in the pound as British companies become ripe takeover targets".
"The pound is down around 10 per cent since the referendum and this makes British firms a lot more attractive," he added.
May is making her first visit to Wales as Prime Minister today, to meet with the Welsh First Minister Carwyn Jones.
Last week saw the new PM pledge to put big businesses under the microscope with plans to introduce completely binding shareholder votes on executive pay and force companies to publish their pay ratios.