(Bloomberg) -- Blackstone Group LP plans to convert to a corporation from a publicly traded partnership, a step that opens up the stock for inclusion in indexes, after watching two rivals benefit from the move. The shares jumped in early trading.

“We believe the decision to convert will make it significantly easier for both domestic and international investors to own our stock and should drive greater value for all of our shareholders over time," Stephen Schwarzman, chief executive officer of the world’s largest alternative asset manager, said in a statement Thursday.

Private equity firms including Blackstone have seen their stock prices lag since going public even as investors have poured money into their buyout, credit, real estate and other funds.

Blackstone has epitomized the industry’s fundraising muscle. The New York-based company also reported Thursday that its assets under management crossed half a trillion, to $512 billion, for the first time.

KKR & Co. and Ares Management Corp. announced conversion plans last year following the passage of a U.S. tax law, which cut the corporate rate to 21 percent from 35 percent. The switch makes it possible for these firms to be included in indexes, which could potentially boost stock valuations and win more mutual fund and ETF investors. It also eliminates the need for investors to file cumbersome K-1 tax forms.

KKR’s stock initially outperformed its biggest rivals after its May 2018 announcement that it was converting to a C-corp. Shares of Blackstone popped toward the end of last year and have beat KKR since revealing its conversion plans through Wednesday.

Blackstone’s stock price has risen about 21 percent this year. The shares jumped about 9 percent in pre-market trading Thursday.

Still, inclusion in indexes isn’t guaranteed because there is some subjectivity in the decision, said Gerald O’Hara, an analyst at Jefferies.

“You can check all the boxes, but still not get included,” he said.

Blackstone said it expects the conversion to be effective as of July 1.

--With assistance from Melissa Karsh.

To contact the reporter on this story: Heather Perlberg in Washington at hperlberg@bloomberg.net

To contact the editors responsible for this story: Margaret Collins at mcollins45@bloomberg.net, Vincent Bielski

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