Signage is displayed outside of a Bed Bath & Beyond Inc. store in Los Angeles, California, U.S., on Monday, Sept. 19, 2016.

Bed Bath & Beyond shares rocketed more than 22 percent Tuesday as three different activist investors prepare to replace its entire 12-person board.

Legion Partners Asset Management, Macellum Advisors and Ancora Advisors will try to leverage their collective 5 percent stake to launch a proxy fight at the big-box retailer, according to a person familiar with the situation.

The coalition believes the company has fallen behind as more customers pivot to online shopping and allowed its costs to drift higher in recent years, the person added. It also hopes to oust Chief Executive Steven Temares, who has led Bed Bath & Beyond since 2003.

"Members of our Board of Directors and senior management team have met with and held several discussions with Legion and Macellum over the past few weeks. Ancora has not previously reached out to or engaged," Bed Bath & Beyond said in a press release.

"We asked on several occasions for their suggestions and ideas for improving the Company's business but they did not provide any. We also invited them to participate in the Board refreshment program we have been undertaking in recent years and are in the process of accelerating with investor input," the company added. "Instead they chose to publicly attack the Company and provide their intent to nominate directors to take over the full Board. Unfortunately, while our directors and management were seeking to engage in good faith, it appears that the Legion and Macellum representatives were merely seeking information to support their attack."

The activist trio isn't pushing for a sale of the entire company, another person familiar with the situation told CNBC. Instead, they'd like to see Bed Bath & Beyond consider sales of underperforming assets such as Buy Buy Baby and decor retail chain Cost Plus World Market.

Raymond James upgraded the stock in light of the news, with analyst Bobby Griffin writing that "within the foreseeable future, Bed Bath & Beyond may either no longer be a public company or [go] on a journey to go private."

"The arguments that have caused investor antipathy to Bed Bath & Beyond are real and center on the tired nature of its nearly 1,000 North American Bed Bath & Beyond stores," Griffin added. "Irrespective of the elevated capital investment of the past several years, management has been slow to invest in its stores."

"Meanwhile, too many of the stores we have visited in a wide variety of states over the last few months are cluttered and dirty. This will likely add credibility to any activist style campaign," Griffin told clients.