Stocks making the biggest moves premarket: Constellation Brands, Palantir, Norwegian Cruise and others
Check out the companies making headlines before the bell:

Constellation Brands (STZ) – The maker of beer and wine reported adjusted quarterly earnings of $2.38 per share, missing the $2.77 consensus estimate, although revenue did beat Wall Street forecasts and Constellation increased its full-year earnings outlook. Shares fell 2.2% in the premarket.

Acuity Brands (AYI) – The maker of lighting and building management systems reported an adjusted quarterly profit of $3.27 per share, beating the consensus estimate of $2.85, with revenue topping forecasts as well. The earnings beat came amid what the company terms a "challenging" environment that included higher labor, materials and freight costs.

Palantir Technologies (PLTR) – Palantir surged 8.1% in the premarket following news that it won an $823 million Army contract to provide its Gotham platform, an operating system designed to optimize defense decision-making.

Norwegian Cruise Line (NCLH) – Norwegian CEO Frank Del Rio told CNBC's Closing Bell that the company would have its full fleet in operation by April for the first time since the pandemic began. He said 75% of ships should be sailing by the end of this year. Norwegian shares fell 1.7% in premarket trading.

Seagate Technology (STX) – The disk drive maker's shares slid 3.3% in the premarket after Morgan Stanley downgraded the stock to "equal weight" from "overweight," citing deteriorating industry data including rising inventory levels and a drop in corporate spending plans.

General Motors (GM) – The automaker's shares will be on watch today as GM holds its investor day, set to highlight its plans for electric vehicle growth.

Southwest Gas (SWX) – Southwest Gas struck a deal to buy Questar Pipelines from Dominion Energy (D) for $1.975 billion in cash and assumed debt. Investor Carl Icahn, who holds a 4.9% stake in Southwest Gas, had sent a letter to the company objecting to such a deal when reports of it first surfaced earlier this week. Icahn said the deal would be a huge mistake and diminish shareholder value. Southwest Gas fell 1.7% in premarket action.

Facebook (FB) – Facebook CEO Mark Zuckerberg responded to accusations from whistleblower Frances Haugen, saying the company does not prioritize profits over safety. Zuckerberg published a blog post addressing the accusations following Haugen's testimony before a Senate panel Tuesday. Shares shed 1.3% in the premarket.

Manchester United (MANU) – Manchester United announced a 9.5 million share offering by the Glazer family, which controls the soccer club. Manchester United will not receive any proceeds from the sale. The stock tumbled 9.4% in premarket action.

HSBC Holdings (HSBC) – HSBC was upgraded to "buy" from "neutral" at UBS, which points to an attractive valuation and optimistic 2022 expectations for the bank's financial performance. The stock added 2.3% in the premarket.