Source: Sharecast
In a brief statement, the inspection, product testing and certification company said the unsolicited, indicative cash proposal was received on 10 April.
"The board of Intertek carefully reviewed EQT's proposal with its advisers and unanimously concluded that it fundamentally undervalues Intertek and its future prospects," it said. As a result, the proposal was rejected on 13 April.
In a statement earlier in the day, EQT said it was "considering its options" following the rejected proposal.
The PE firm said there can be no certainty that an offer will be made nor as to the terms on which any offer might be made.
Under UK takeover rules, it has until 1700 BST on 14 May to either announce a firm intention to make an offer or walk away.
At 1400 BST, Intertek shares were up 12.6% at 4,914p.
On Tuesday, Intertek announced that it was mulling splitting into two businesses. The company said it had launched a strategic review to evaluate the creation of two specialist businesses, Intertek Energy & Infrastructure and Intertek Testing & Assurance, either by demerger or a sale.
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