Early movers: WEN, LUV, LOW, UNH, MMM, MU, K, MA & more

Check out which companies are making headlines before the bell:

Wendy's (WEN) – Nelson Peltz's Trian increased its stake in the restaurant chain to 23.45 percent from the prior 15.6 percent.

Southwest Airlines (LUV) – The air carrier reported a 7.2 percent increase in revenue passenger miles in November from a year earlier.

Lowe's (LOW) – The home improvement retailer reiterated its prior guidance for fiscal 2016 prior to its meeting with analysts and investors Wednesday in Mooresville, North Carolina.

UnitedHealth Group (UNH) – The health insurer was upgraded to buy from hold by Cantor Fitzgerald, which points to an upbeat outlook at last week's investor day. Cantor said the stock has room to move higher despite a 34 percent year-to-date gain, due to factors including market share gains and the elimination of exchange losses.

3M (MMM) – RBC upgraded the Dow component to sector perform from underperform, with a recent drop in the stock making its risk/reward profile more balanced. RBC does say that health care exposure could hurt 3M due to possible new Trump initiatives, but it is raising its price target for 3M to $171 from $155.

Micron Technology (MU) – Citi began coverage on the chipmaker with a buy rating, pointing to rapidly improving fundamentals in the DRAM industry.

Kellogg (K) – Credit Suisse removed the cereal maker from its US Focus List, and now rates it neutral. Credit Suisse said Kellogg's revenue growth continues to underperform that of its peers, and that moves to counter slowing growth have yet to pan out.

MasterCard (MA) – The credit card issuer announced a 16 percent increase in its quarterly dividend, to 22 cents per share from the prior 19 cents. MasterCard also announced a new $4 billion share repurchase program.

Dave & Buster's Entertainment (PLAY) – The company reported adjusted quarterly profit of 25 cents per share, beating estimates by 11 cents. The arcade and casual dining chain also saw revenue beat forecasts, and it raised its full-year revenue guidance .

Western Digital (WDC) – Western Digital raised its fiscal second quarter revenue guidance to $4.75 billion from the prior $4.7 billion, and raised its earnings forecast. The hard disk drive maker cited more customer enthusiasm for its product mix and revenue from a new cross licensing agreement with Samsung, among other factors.

Pfizer (PFE) – Pfizer was hit with a record $107 million fine by British officials for an epilepsy drug price increase of as much as 2,600 percent. The drugmaker said it plans to appeal the decision, and said the price was actually 25 to 40 percent less than the equivalent drug from an alternate supplier.

Sony (SNE) – Sony plans to releases as many as six mobile phone gains in the upcoming fiscal year, as it tries to duplicate the success that rival Nintendo has seen with "Pokemon Go."

Starbucks (SBUX) – Starbucks will be unveiling more details about its new upscale "Reserve" coffee bars at an analyst meeting in New York on Wednesday.

Apple (AAPL) – The company said Apple Pay transactions are up 500 percent over a year ago, with apparel retailer Gap the latest to add the service. That's according to Apple executive Jennifer Bailey, speaking at a Recode event. And Apple Music subscriber rolls now total 20 million, compared with 17 million in September, according to a Billboard report.

Fitbit (FIT) – Fitbit is near a deal to buy rival fitness device maker Pebble, according to Bloomberg, although the report said a deal will focus on Pebble's software assets.