Macy’s is embroiled in a legal battle with its landlord to prevent Amazon from marketing on a billboard that sits on top of its most iconic flagship store.

The department store chain is asking New York City-based Kaufman Organization to stop a potential deal with Amazon to use the billboard atop its storied Herald Square location, according to a lawsuit filed in state Supreme Court in Manhattan.

According to the complaint, Macy’s claims that advertising from an online competitor will cause it “immeasurable” damage.

In court documents that Macy’s filed and which were examined by CNBC, Macy’s stated, “The damage to Macy’s customers goodwill, image reputation, brand, and reputation should a prominent internet retailer (especially Amazon), advertise on the billboard is impossible to calculate.”

Macy’s has had the billboard advertising for more than fifty years. Macy’s claimed that Kaufman failed to reach an agreement after the August lease expired. According to the complaint, Kaufman had already been in negotiations with Amazon at that time.

Macy’s maintains that it was in talks with Amazon at that point.

CNBC reached out to representatives of Amazon and Kaufman Organization for comments but they did not respond immediately.

“Since the early 1960s Macy’s has placed a billboard sign on the building adjacent to our flagship store at the corner of Broadway and 34th Street,” a spokeswoman for Macy’s told CNBC in an emailed statement.

She stated that Macy’s retains rights in relation to advertising at this location. We are confident that we will realize the full benefits of these rights. Therefore, we asked the court for protection. The company won’t comment further as the case is still in court.

Crain’s New York first reported Follow the court battle.