Erez Asset Management has disclosed ownership of 10 million shares in Empire State Building Trust, a position representing 5.8 percent of the REIT.

The New Rochelle, N.Y.-based activist investment firm and hedge fund manager has moved quickly to press ESRT’s leadership to consider selling assets, according to reporting by Commercial Observer.

The stake introduces another activist voice at ESRT, placing renewed attention on management’s approach to capital allocation and the potential role of property disposals in its strategy.

For investors and commercial real estate market participants, the disclosure will be closely watched for any response from ESRT’s board or further detail from Erez on the changes it wants the company to pursue.