By Kit Norton

Shares of Charter Communications surged on Monday, leading the S&P 500 for the trading session, and the two big catalysts behind the move were SpaceX and Comcast.

Charter stock rose 11% to $148.18 on Monday, set to notch its best daily percentage gain in more than a year, according to Dow Jones Market Data.

Investors were pushing shares of Charter Communications higher after Bloomberg reported late Friday that the operator of Spectrum Internet services has held high-level discussions with SpaceX about possibly partnering on a consumer mobile phone.

Charter Communications declined to comment to Barron's. SpaceX didn't respond to a request for comment.

There's long been speculation that Elon Musk might enter the mobile phone market, challenging Apple and Alphabet in the space. However Musk has repeatedly shut down rumors that Tesla would produce a phone. Now it looks like SpaceX could be the phone manufacturer in Musk's business empire.

Charter Communications, Comcast, AT&T, and Verizon Communications have all come under pressure from SpaceX's Starlink business, the provider of satellite Internet services which currently has about 12 million subscribers.

If Charter was to partner with SpaceX on a mobile phone, it would give the company exposure to Musk's Starlink business and growing subscriber base.

However the possibility of Charter Communications being a SpaceX mobile phone partner wasn't the only reason shares were moving higher.

Charter Communications and Comcast are the two leading cable Internet providers in the U.S. and there was some pretty big news about Comcast on Monday.

Comcast announced plans to split into two companies, one focused on technology and the other on media, by spinning off NBCUniversal and Sky. Michael Angelakis, who has formerly served as Comcast's chief financial officer, will become the CEO of the Comcast business focused on its broadband, wireless and remaining entertainment operations.

The move signals a large shift in the landscape of cable Internet providers. It also raises the possibility that Comcast could potentially acquire Charter Communications to solidify itself as the top provider in the U.S.

Comcast stock rose 6.3% to $24.64 Monday, while AT&T and Verizon declined 5.6% and 7%, respectively. T-Mobile stock fell 5%. SpaceX already offers direct-to-cell connectivity with T-Mobile in the U.S.

Write to Kit Norton at [email protected]

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