Straight Path Communications has received an unsolicited offer from what it’s calling “a multi-national telecommunications company,” that Straight Path says is a “superior proposal” to the offer AT&T made for the company earlier this month.

The unnamed bidder is offering about $200 million more than AT&T. The new bidder has offered $104.64 per share, reflecting a value of $1.8 billion, which the bidder would pay with its own stock. This compares to the AT&T agreement to acquire Straight Path in an all-stock transaction for $95.63 per share, reflecting a value of $1.6 billion.

AT&T wants the company’s nationwide portfolio of millimeter wave (mmWave) spectrum licenses, which are primarily in the 39 GHz and 28 GHz bands and cover the top 40 markets in the U.S. The spectrum is an important element of AT&T’s 5G goals.

Although the new bidder is unnamed, reports have circulated for the past week that the mystery company is Verizon. Both AT&T and Verizon could benefit from locking down Straight Path’s spectrum assets and shutting the other out before any high-band spectrum auctions begin in the U.S.

AT&T has five business days to negotiate a new offer that matches or exceeds the latest bid. But if Straight Path chooses the unnamed bidder it would have to pay a $38 million termination fee to AT&T. However, the new bidder has agreed to pay the termination fee on Straight Path’s behalf, in such an event.