Stocks making the biggest moves premarket: VZ, TSLA, AAPL, WFC, T, SIRI & more

Check out the companies making headlines before the bell:

Verizon – The telecom giant's stock was upgraded to "buy" from "hold" at Deutsche Bank, which said fundamentals are improving but the stock price hasn't yet caught up. Deutsche Bank points to potential from 5G technology and an improving wireless business, among other factors.

Tesla – CEO Elon Musk sent an email to workers saying an unnamed employee had engaged in "extensive and damaging sabotage." Musk said the automaker is investigating whether the employee was working with any outside organizations.

Apple – Apple's iPhones would not be subject to new tariffs on phones assembled in China, according to a New York Times report. The paper said President Donald Trump had made that commitment to Apple CEO Tim Cook in a meeting last month.

Wells Fargo – The bank is considering a combination of its private client and wealth brokerage services units. Both divisions target affluent clients and many of their functions overlap.

AT&T – AT&T is promising fewer commercials, smaller channel bundles, and personalized programming following its buyout of Time Warner, according to a Reuters interview with John Stankey, chief executive of the newly renamed WarnerMedia unit. However, J.P. Morgan Securities downgraded the stock to "neutral" noting that strategy will take a few years to provide financial benefits.

Foundation Medicine – Foundation Medicine is being bought out by Swiss drug giant Roche in a $2.4 billion deal worth $137 per share. Roche had already owned 57 percent of the U.S.-based molecular diagnostic test maker.

Sirius XM Holdings – Sirius XM was downgraded to "hold" from "buy" at Pivotal Research in a valuation call. Pivotal's target price for the satellite radio operator's stock remains at $7.75 per share.

Intuit – Intuit was upgraded to "buy" from "hold" at Stifel Nicolaus, which also increased its target price on the financial software maker's stock to $240 per share from $197. Stifel cites improving competitive dynamics at the two primary business divisions, Consumer Tax and QuickBooks Online.

Dr Pepper Snapple – Stifel Nicolaus cut its rating on the beverage maker to "hold" from "buy," noting the stock's 25 percent run-up this year and the potential impact of higher packaging and logistics costs. Dr Pepper is in the process of combining itself with Keurig Green Mountain, with a shareholder vote coming next week.

KKR – The private-equity firm is exploring the sale of European telecom operator United Group, according to The Wall Street Journal, in a deal that could value the company at up to $3.47 billion.

Amazon.com – Amazon has introduced a version of its Alexa virtual assistant for the hospitality industry, aimed at increasing guest access to amenities as well as helping to improve employee productivity.

Mattel – The toy maker was downgraded to "neutral" from "buy" at UBS, which still sees value in the Mattel brand but notes the stock's 35 percent jump from its March lows despite little change in fundamentals.