Another group of activist shareholders in the nation’s largest senior living provider is urging the company to monetize its assets through a major real estate sale.

The group, Stamford, Conn.-based Land and Buildings Investment Management LLC, stressed Brookdale Senior Living’s (NYSE: BKD) options in a letter to the company’s shareholders Tuesday, indicating that shares of Brookdale stock have a net asset value of at least $25 per share versus the current share price of around $12.72. That value could be unlocked through a sale of the company’s owned real estate, Land and Buildings writes, leading to a transition of the company to an “asset light” senior housing management company.

By Land and Buildings’ estimate, the net real estate value of Brookdale’s owned properties is around $4 billion.

“Brookdale Senior Living shareholders have endured one misstep after another on the part of BKD’s management and Board of Directors over the past several years, and nearly 70% of shareholder value has been eviscerated in the past 18 months,” the letter to shareholders reads. “…As we have communicated to the Brookdale management team and Board in numerous discussions and letters over the past several months, the Company must act with urgency to crystalize value.”

The letter is signed by Jonathan Litt, founder and CIO of Land and Building Investment Management, who also wrote a recent letter criticizing the “management cronies” involved in the $17 billion merger of three major real estate companies including NorthStar Asset Management (NYSE: NSAM), NorthStar Realty Finance (NSYE: NRF) and global real estate firm Colony Capital Inc. (NSYE: CLNY).

“Brookdale’s Board and management appreciate and value constructive input from shareholders, consistent with our goal of increasing shareholder value,” the company said in a statement. “Brookdale’s Board is carefully evaluating Land and Building’s letter and the Company remains open to continuing our dialogue with Land and Buildings.”

Land and Buildings is not the first activist shareholder group to target Brookdale’s share value. In February 2015, Sandell Asset Management penned a similar letter urging Brookdale to spin off the Brentwood, Tennessee-based provider’s owned real estate portfolio into a REIT, a move that the group urged would unlock intrinsic value for shareholders.

Sandell later sold its stake in the company.

The latest letter cites recent billion-dollar senior housing transactions as giving way to a selloff of Brookdale’s real estate, including NorthStar Realty Finance’s (NYSE: NRF) sale of a non-controlling stake in more than $2 billion worth of senior housing to Taikang Insurance Group; Welltower’s (NYSE: HCN) sale of $1.2 billion in non-core, senior housing assets; and HCP’s (NYSE: HCP) sale of $1.125 billion of below average quality Brookdale senior housing assets to Blackstone.

“In this favorable climate, we see a clear path to value realization and a leaner, more efficient, asset-light Brookdale,” Litt writes. “Sell the Company’s owned real estate and distribute proceeds to shareholders, and become an asset-light senior housing management company by converting existing leases to management contracts.”

Written by Elizabeth Ecker