01/12/2014 at 01:00 PM EST
Going once, going twice ... sold to Anderson Cooper – for $1.4 million!
Celebrities didn't hold back for the live auction during Sean Penn's Help Haiti Home gala held Saturday night
– especially when it came to a coveted customized piece from renowned contemporary artist, Jeff Koons.
The high-priced prize, which will be created using Penn's collection of old firearms, had Cooper reaching deep into his pockets. But, after a fierce bidding battle with Piers Morgan – who bowed out after offering $1.3 million – it was Cooper who finally took home the grand prize.
"During the auction, Gwyneth Paltrow
was screaming at Anderson to go for it!" an eyewitness tells PEOPLE.
While the host of the night was thrilled with his winnings, maybe he should have first checked in with his boyfriend, Benjamin Maisani? According to the journalist, his partner was suffering from a case of sticker shock over the promised artwork.
"I texted my boyfriend and told him I spent $1.4 million on a piece of art. He said, 'Are you f------ kidding!?' " Cooper, 46, joked to the crowd later in the night.
The evening raised $6 million in total
and other celebrity guests included Chris Martin, Julia Roberts, Danny Moder, Kevin Bacon, Michael Douglas, Emma Thompson, Bette Midler, U2, Chris Hemsworth
and Diane Kruger.
Reporting by MATTHEW COLE WEISS