Check out which companies are making headlines before the bell:
Microsoft – Canaccord upgraded Microsoft to "buy" from "hold" based on prospects for long-term growth acceleration, and on the idea that investors have underestimated the cyclical benefits of Microsoft's growth drivers in multiple areas.
CarMax – Oppenheimer cut its rating on the car retailer to "perform" from "outperform," citing more challenging used car sales comps, among other factors.
SeaWorld Entertainment — Both Reuters and Bloomberg reported that U.K. theme park operator Merlin Entertainments had approached SeaWorld about a potential bid. Merlin is bidding for just part of SeaWorld, but SeaWorld is said to prefer a sale of the entire company.
Sonic – Sonic said its systems were compromised by a malware hack which may have allowed access to customer credit card information. The breach at the restaurant chain was first reported by cybersecurity blog KrebsOnSecurity last week.
Verizon – Verizon media chief Marni Walden is leaving the company in February, with her responsibilities divided among existing executives. The Wall Street Journal is reporting that Walden decided to leave after it became clear she was unlikely to become Verizon's next CEO.
ADP – ADP is on watch today after activist investor Bill Ackman told CNBC that the payroll processing firm should be more productive than its competitors given its scale. Ackman is in the midst of a proxy fight, trying to gain seats on the board of directors.
Apple – Apple rolled out a software update for the latest version of its Apple Watch, addressing some cellular connectivity issues that have affected users.
Inovio Pharmaceuticals – Inovio saw its experimental Zika vaccine – developed in conjunction with South Korea's GeneOne Life Science – show promise in an early human trial, prompting anti-Zika immune responses in patients.
Alphabet — A subsidiary of the Google parent is nearing a deal to develop a high-tech urban area near Toronto's waterfront, according to The Wall Street Journal.
Cigna – Cigna ended health insurance coverage for opioid painkiller OxyContin. The change will take effect January 1, with Cigna switching its coverage to Collegium Pharmaceutical's extended-release oxycodone equivalent known as Xtampza ER. That treatment is less vulnerable to user abuse.
Coach – The luxury goods maker was downgraded to "neutral" from "overweight" at Piper Jaffray, which cited the ongoing integration of Kate Spade and process of analysts becoming more comfortable with new reporting segments.
Norwegian Cruise Line – Norwegian will replace Level 3 Communications in the S&P 500 when the acquisition of Level 3 by CenturyLink is completed. The change is expected to occur before the opening of trading on Friday, October 13.
Mastercard, PayPal – The two companies expanded their partnership to include Canada, Europe, Latin America, the Caribbean, the Middle East, and Africa. The agreement presents Mastercard as a payment option within the PayPal wallet.
Zumiez – Zumiez reported a better-than-expected September comparable sales rise of 9.3 percent, with the seller of action sports apparel also predicting current-quarter revenue above current Street forecasts.