Donald Trump's victory in the presidential campaign throws doubt on AT&T Inc.'s proposed acquisition of Time Warner Inc. and could undermine the government's net neutrality rules. But many of his positions on the technology and telecommunications sectors are largely unknown.

Mr. Trump said in October that he would block the AT&T-Time Warner deal, and that he would try to break up the Comcast Corp.-NBC Universal merger. In both cases, Mr. Trump said the media is controlled by too few people.

Shares of AT&T fell 2% in early premarket trading while Time Warner shares, which were already trading at a wide discount to AT&T's offer, fell 4.4%.

Mr. Trump also made statements against net neutrality, saying it would "target conservative media" and comparing it against the Fairness Doctrine, which required broadcasters on government airwaves to provide balanced coverage of controversial issues. (Net neutrality requires all web traffic be treated equally but doesn't involve content.)

Analysts at New Street Research believe Mr. Trump will likely align with traditional Republican thinking on telecom policy. Particularly on complex, low-publicity items, "partisan gravity will be sufficient to bring Trump's view into line with his party's well-established path," researchers wrote in a note to clients earlier this year.

It would be difficult, but not impossible, for Mr. Trump to unwind the Federal Communications Commission's 2015 net neutrality rules. Those rules were upheld by a Washington, D.C., appeals court, but the telecom industry has appealed to the Supreme Court. If the court agrees to hear the case, and Mr. Trump is able to appoint conservative judges, it is plausible the rules could be overturned.

More than a year ago, after Mr. Trump began his presidential campaign, the New Street Research analysts published a tongue-in-cheek research note about the impact his presidency would have on the U.S. telecom market. The note joked about how AT&T and Verizon Communications Inc. would succeed under a Trump presidency because "They are big. They are huge. They are tremendous."

New Street Research sent outa revised note a few months later after Mr. Trump began winning states in the Republican primary. We "thought the prospect of a Trump presidency quite low," they wrote.

Analysts at Citigroup say Mr. Trump's victory could affect some media stocks as his embrace of social media boosts Twitter Inc. and Facebook Inc., while his confrontational relationship with traditional outlets hurts CBS, Disney, Time Warner and Fox.

Likewise, Mr. Trump's stance on net neutrality could help cable companies like Comcast Corp. and Charter Communications Inc. but hurt over-the-top players like Netflix Inc., Citigroup said.

Thomas Gryta contributed to this article.

Write to Ryan Knutson at ryan.knutson@wsj.com

(END) Dow Jones Newswires

November 09, 2016 08:25 ET (13:25 GMT)

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