The Upper Deck Co. said on Monday it would launch a hostile tender offer to acquire baseball trading card company Topps Co. Inc. for about $425 million.

Upper Deck, which publishes sports trading cards and other memorabilia, said its $10.75 per share offer was superior to Topp's existing deal to be acquired for $9.75 per share by a private equity firm and an investment group led by former Walt Disney Co. chief Michael Eisner.

Upper Deck said its cash offer is not conditioned upon any financing arrangements.

Topps could not be immediately reached for comment.

Topps previously criticized Upper Deck for offering no evidence of how it would finance the deal. Topps also has slammed Upper Deck's offer as having higher regulatory risk and an inadequate break-up fee in the event the deal fails to close.

Topps' $385 million agreement to be acquired by Madison Dearborn Partners and Tornante Co., the firm run by Eisner, had drawn criticism from a member of the Topps board and activist hedge fund Crescendo Partners. Opponents said the price was too low and the auction process had been flawed.

Last week, Topps postponed its June 28 shareholder meeting to vote on the takeover. The Delaware Court of Chancery had prevented Topps from proceeding with the stockholder vote until the company made additional public disclosures about the pending deal.

Topps also granted a waiver that freed Upper Deck from a standstill agreement and allowed it to proceed with the tender offer.

Shares of Topps closed at $10.51, down 6 cents, on Nasdaq.