What happened

Shares of Adtran (NASDAQ:ADTN) plunged today, and are down by 22% as of 11:35 a.m. EDT, after the networking equipment company announced preliminary fiscal third-quarter earnings estimates that were well below the market's expectations.

So what

Revenue in the fiscal third quarter should be approximately $114 million, compared to the consensus estimate of $140.2 million in sales. That should translate into an adjusted loss per share of $0.06, while analysts were modeling for $0.03 per share in adjusted profit. In a statement, CEO Tom Stanton explained the shortfall:

Our revenue this quarter has been significantly impacted by a pause in shipments to a Tier 1 customer in Latin America and the continued slowdown in the spending at an international Tier 1 customer. With the exception of these two large customers, revenues generated from the rest of our business grew 20% over the previous quarter. Although we expect our Latin American customer sales to rebound, our current visibility regarding timing is limited. For the international Tier 1 customer, we expect that sales should resume with the new capital cycle in 2020.

Red stock chart  with a red down arrow in the middle.

Image source: Getty Images.

Now what

MKM Partners analyst Michael Genovese downgraded Adtran shares from buy to neutral following the news, clarifying that the top-line miss was attributable to reduced orders at Deutsche Telekom and the pause in shipments relates to Telmex. MKM reduced its price target from $17 to $11.

Adtran also provided an outlook for the fiscal fourth quarter, with revenue expected to be flat to slightly down on a sequential basis. Adjusted operating expenses should be roughly 10% lower than adjusted expenses in the second quarter.