The deal gives Intu the half share in the Brierley Hill-based shopping centre that had been owned by Westfield.
The other half is retained by Australian investment group QIC. The agreement is part of a £867.8m property deal that sees Intu take over complete ownership of Westfield's Derby shopping centre and Sprucefield retail park in Northern Ireland.
David Fischel, chief executive of Intu, said he was delighted to establish the partnership with QIC at Merry Hill. "The transaction is a rare and attractive opportunity to acquire a further two prime shopping centres in line with our strategy to focus on the UK's largest and most successful destinations," he said.
"The acquisition strengthens Intu's position as the leading owner, developer and manager of prime UK shopping centres filling in gaps in our national coverage and extending the footprint of our nationwide consumer facing brand and digital strategy. We are delighted to establish a partnership with QIC, a major global investor, at Merry Hill."
The 1.4 million sq ft shopping centre now joins the likes of Manchester's Arndale and Trafford centres in the Intu's 18 million sq ft stable of retail and leisure sites, valued before today's deal at £7.6 billion. They include 17 of the UK's top 25 shopping destinations.
Westfield had owned the centre since 2004 following the takeover of previous owners Chelsfield.
Westfield Group co-CEO Steven Lowy, said: "Today's announcement continues the strategic repositioning of the international portfolio in line with our focus on investing and operating iconic retail destinations in major world cities."
Intus says the three sites will generate annual rents of £54.9 million to £22.6 million from Merry Hill alone.