Yahoo Inc said it is on track to spin off its nearly 15 percent stake worth about $22 billion in China-based Alibaba Group Holding Ltd this year into a separate corporate entity called Aabaco Holdings Inc.

The move is aimed at assuaging investor concern about a multi-billion-dollar tax hit from the transaction. Yahoo's board authorized the spinoff, even though the United States Internal Revenue Service declined to grant the company an advance ruling blessing the deal, it said in a filing on Monday.

While the agency is stepping up scrutiny of such transactions, Yahoo is going forward with the plan, which was announced in January, after the IRS indicated a decision is not likely to be retroactive.

Marissa Mayer, Yahoo's chief executive officer, is seeking to address doubts on Wall Street about how she is managing the company's assets. She is aiming to spin off the Alibaba stake and potentially save about $9 billion in taxes.

Analysts have questioned for months whether the tax issue would stop Mayer from completing the proposal.

"Neither this ongoing guidance project nor the IRS's decision not to rule with respect to the Aabaco spinoff transaction changes the current law applicable to the proposed spinoff," Yahoo said in a filing.

Yahoo also noted that an IRS official indicated this month "that any future guidance issued as part of the project would not apply retroactively to transactions completed prior to the issuance of such guidance."

Yahoo's shares rose as much as 4.3 percent in extended trading on Monday, but declined 5.3 percent to $27.60 at the close in New York. Alibaba's shares fell 3.1 percent to a record low at $57.39.

Yahoo also said the spinoff will be listed on Nasdaq under the ticker symbol AABA. The company will include the small business unit of Yahoo as part of the transaction.

Sarah Meron, a spokeswoman for Sunnyvale, California-based Yahoo, did not immediately return a voice mail seeking comment.