Sapna Maheshwari
Bloomberg News

American Greetings Corp., the biggest publicly traded greeting-card company, said Wednesday that Chief Executive Officer Zev Weiss and Chief Operating Officer Jeffrey Weiss offered to take the card-maker private for $17.18 a share.

The board will form a special committee to consider the proposal, the Cleveland-based company said in a statement. The offer was 20 percent higher than the shares’ closing price of $14.34 on Tuesday. The stock rose 17.3 percent to $16.82 in Wednesday trading. It climbed as much as 19 percent for the biggest intraday gain since September 2009.

The Weiss brothers said in a letter Tuesday that they want to return American Greetings, which was founded more than a century ago and became publicly traded in 1958, to its roots as a family-owned enterprise.

Revenue at the company, which counts Wal-Mart Stores Inc. and Target Corp. as its biggest customers, rose 6.1 percent to $1.7 billion in the year ended Feb. 29.

The transaction “provides the public stockholders of the company with liquidity and certain value in a highly volatile period in the equity markets,” the brothers said in the letter. “We anticipate maintaining intact American Greetings employee base, which we view as its most important asset, and current senior management.”

The company said various foundations and members of the Weiss family will reinvest or roll over “substantially all of their shares” in the acquiring entity, and that it would obtain debt financing for the balance of the purchase.

Hedge fund Marathon Asset Management LP is the largest holder of the company’s publicly traded Class A shares, with 17 percent of the stock outstanding, according to data compiled by Bloomberg News. The company had 30.9 million Class A shares outstanding as of July 2, and 2.86 million Class B shares, which are more than 90 percent owned by the Weiss family, according to company filings.

American Greetings, which competes with closely held Hallmark Cards Inc., sells cards under brand names such as Carlton Cards and Papyrus, as well as gift packaging, party goods and stationery, the filing said. More than 80 percent of Americans buy greeting cards each year, American Greetings has said. The company got 72 percent of its revenue from the U.S. in its most recent fiscal year.

American Greetings had $225.2 million of long-term borrowings and $60.2 million in cash and equivalents as of May 25.

The shares had gained 15 percent this year through Tuesday.