Burger King (BKC) reported a 23% rise in first-quarter earnings, topping expectations, as movie tie-ins and new menu items helped boost traffic.

But the Miami-based burger chain also said its top stockholders plan to unload up to a third of their shares, putting pressure on the stock early Monday.

For the quarter ended Sept. 30, Burger King earned $49 million, or 35 cents a share, up from $40 million, or 30 cents a share, a year earlier.

Analysts anticipated earnings of 33 cents a share for the latest quarter, according to Thomson Financial.

Burger King's revenue rose to $602 million from $546 million a year earlier, beating analysts' estimate of $597 million.

Same-store sales, or sales at restaurants open at least a year, rose 5.9% worldwide. In the U.S. and Canada, they jumped 6.6%.

Burger King said new menu items like its "Tendercrisp" and "Spicy Chick'N Crisp" sandwiches helped drive revenue gains, while tie-ins with

The Simpsons

and

Transformers

movies brought in more traffic.

Separately, Burger King said private-equity firms TPG Capital, Bain Capital and Goldman Sachs Funds plan to sell 23 million shares on the public market. The firms, which took the company public last year, also plan to grant underwriters the option to buy an additional 3.45 million shares to cover over-allotments.

The three firms currently own 79 million Burger King shares, equal to a 58% stake. After the offering, the firms are expected to own a 41% stake in Burger King, or 38% if the over-allotment is exercised in full.

Shares of Burger King recently were down 85 cents, or 3%, to $26.89.