These two firms also happen to be the banking advisers to Brazilian steelmaker CSN, which is competing with India's Tata Steel for acquiring Corus.
UBS AG acting through its business group and legal entities has picked up 66.12 million shares of Corus Group, representing 7.36 per cent, as per information available on the Corus website.
Goldman Sachs Group Inc acquired 36.06 million shares of Corus, aggregating to 4 per cent stake. CSN has already acquired 3.8 per cent stake in Corus through open market transactions.
Although their combined holding adds up to 15.16 per cent in Corus, the takeover clause on launching an open offer may not apply for them as they have picked up stake separately.
Meanwhile, investment banking sources said that the Tata Steel Board has decided to "match" CSN as and when it makes a formal bid for Corus after due diligence.
CSN started the due diligence early this week and is expected to make a formal bid at 475 pence per Corus share.
In Mumbai, however, Tata Steel said in a statement that it has not taken any decision in the manner speculated (about raising its offer for Corus) in the media at its board meeting held on Thursday.
"Tata Steel is not making any other comments on this matter and all media comments remain speculations," it said.
The Indian company had in October made a $8.1 billion takeover offer, but Brazil's Companhia Siderurgica Nacional SA trumped Tata with a slightly higher offer of $8.3 billion for Europe's second largest steel maker.
