AT&T (T) is in talks to acquire Lumen Technologies’ (LUMN), consumer fiber operations, in a deal that could value the unit at more than $5.5 billion, Bloomberg News reported on Tuesday, citing people with knowledge of the matter.

Shares of Lumen were down more than 14% after the report.

The terms, which are not yet finalized, could change or the talks might still collapse, according to the report.

Both Lumen and AT&T declined to comment on Reuters requests.

The potential move to offload the fiber business, which provides high-speed internet services to residential customers, comes as Lumen is doubling down on the AI boom to power its near-term growth, while grappling with a rapid decline of its legacy business.

Lumen kicked off a process to sell its consumer fiber operations, Reuters reported in December.

The fiber-optic cable provider has over 1,700 wire centers across its total network, with consumer fiber available in about 400 of them.