Shares of

King Pharmaceuticals

(KG)

drifted down Wednesday, a day after the company asked the

Securities and Exchange Commission

for a five-day delay in filing its third-quarter financial statement.

The original deadline is Nov. 15, but King said it needs more time to evaluate the financial impact of past returns of products. King filed its request after markets had closed Tuesday.

Late last month, King revealed that this "high level of returns" could require the company to restate earnings. King attributed the returns to a new inventory management system.

If King restates earnings, it would be a technical violation of an agreement with

Mylan Laboratories

(MYL) - Get Report

. Mylan is seeking to buy King, offering 0.9 shares of Mylan stock for each share of King stock.

Mylan has emphasized that a King financial restatement won't automatically scuttle the deal; the agreement gives Mylan the option to cancel the transaction, which has met with little enthusiasm on Wall Street and a lot of opposition from investor Carl C. Icahn. He has become Mylan's biggest shareholder, owning 9.78% of the shares. Mylan executives have criticized Icahn, who previously disclosed a short position in King's stock, as they have reaffirmed their desire to complete the deal.

Because of the product returns, King has characterized its third-quarter financial results as preliminary. King earned $27.6 million, or 11 cents a share, on revenue of $353.5 million for the three months ended Sept. 30. For the same period last year, King's third-quarter profit was $106.1 million, or 44 cents a share, on revenue of $423.1 million.

King's stock was off 7 cents, or 0.6%, at $11.02 on Wednesday. Mylan's stock was up 11 cents, or 0.7%, to $17.06.