Yahoo’s going ahead with a spinoff — but of its core business, not its holdings in Chinese e-retailer Alibaba, as it had planned.

The strategy, known as a reverse spin, “will provide more transparency into the value of Yahoo’s business,” CEO Marissa Mayer said this morning. Its assets and liabilities, not including its 15% stake in Alibaba, would go into a new company.

alibabaBut the plan seems mostly designed to let Yahoo shareholders take advantage of its $32 billion Alibaba investment without paying taxes on the capital gains. Yahoo shares are up about 1% this morning on the news.

Current Yahoo shareholders would continue to own the stock in the company that would just consist of the Alibaba shares. They also would receive stock in a new publicly traded entity with Yahoo’s core businesses and 35% stake in Yahoo Japan.

The company told analysts in a conference call this morning that it is not considering an outright  sale of the core businesses, mostly ad-supported digital media, which it considers undervalued.

The change could take more than a year as Yahoo seeks approvals from shareholders and the SEC.

Meanwhile, Mayer says, “we will tighten our focus and prioritize investments to drive profitability and long-term growth.”

Yahoo To Announce Q2 Earnings One Day After Appointing New CEOThe Silicon Valley company originally wanted to spin off the Alibaba holdings. But the IRS said in September that it would not guarantee that the deal would be tax-free. Indeed, the agency and Treasury Department said that month that they might look askance at spinoffs designed to avoid taxes.

Wall Street might take a much dimmer view of Yahoo without Alibaba, though. It accounts for about 60% of Yahoo’s stock price, Jefferies Equity Research’s Brian Pitz estimates. Another 14% comes from the Yahoo Japan holding, while 17% comes from the company’s cash.

That suggests investors consider the core operations equal to just 9% of Yahoo’s value — or roughly $3 billion.

That’s an indirect indictment of Mayer’s strategy, since taking charge in 2012, to revive Yahoo’s status as a Silicon Valley icon. She built media properties around brand-name talent including Katie Couric and former New York Times consumer electronics critic David Pogue. She produced longform TV shows including Sin City Saints, Other Space and Season 6 of Community. And she sought to beef up the company with deals including a $1 billion acquisition of Tumblr and $650 million for BrightRoll.

But Yahoo has little to show for those efforts. The company “remains a ‘really, show me’ story,” RBC Capital Markets’ Mark Mahaney said in October after it reported disappointing Q3 earnings — including a $42 million writedown on the video investments. The share price has declined about 30% in 2015.