Google has confirmed plans to issue to issue an additional 5.3 million shares of stock.

The new shares would raise $2.1 billion based on the value of Google's stock at close of trading on Wednesday.

The sale is intended in part to meet the needs of index funds to purchase Google stock once Google is added to the S&P 500 Index on Friday, Google said.

Google will use the money raised for working capital, expenses and possible acquisitions of complementary businesses, technologies or other assets, it said.