Shares of Maguire Properties spiked sharply Monday on a report that an investor had filed a request to buy up to a quarter of its preferred shares.

Michael Ashner, chief executive of Winthrop Realty Trust, has asked Maguire’s board to allow his Boston company to buy up to 25 percent of the Los Angeles REIT’s Series A cumulative redeemable preferred stock. Barron’s reported Saturday on a regulatory filing concerning the request.

Winthrop controls 9.5 percent of Maguire Properties’s preferred shares, according to U.S. Securities and Exchange Commission filings. Maguire currently limits individual shareholders to a maximum of 9.8 percent of the preferred shares.

A spokesperson for Winthrop told Bloomberg News on Monday that it expected a response from Maguire Properties either late Monday or Tuesday.

Maguire shares closed up 35 cents, or 39 percent, to $1.25 on the New York Stock Exchange. In after-hours trading, the stock rose another 11 percent.