Shares of companies specializing in telecommunications, media and entertainment will be combined into a single sector in a major overhaul of U.S. indexes, including the benchmark S&P 500 <.SPX>, S&P Dow Jones Indices and MSCI Inc (>> Msci Inc) said on Wednesday.

The move reflects "an evolution in the way we communicate and access entertainment content and other information," and the dramatic integration of these industries through a wave of mergers and acquisitions, the index operators said in a joint statement.

The new sector schematic will take effect in late September 2018, they said, adding the names of some large companies whose stocks will be impacted by the change will be announced in January.

The index providers did not disclose which companies will be moved to the new Communication Services index.

But a list of candidates could include the so-called FANG stocks - Facebook Inc (>> Facebook), Amazon.com Inc (>> Amazon.com), Netflix Inc (>> Netflix) and Google parent Alphabet Inc (>> Alphabet) - along with traditional telecom or media players, such as AT&T Inc (>> AT&T) and Walt Disney Co (>> Walt Disney Company (The)).

Each of those stocks meets some of the criteria laid out by S&P and MSCI on Wednesday.

The move marks the second major change in just over a year in how stocks are grouped. The index operators in 2016 split real estate investment trusts out from the financial services sector.

"The technology sector is the largest sector of the market, so you're scaling that back. This will be the hot sector of the market then - if it's the type of changes we're talking about," said Michael O'Rourke, chief market strategist at JonesTrading.

"The market sees these names (like Facebook and Google) as leadership. If you start consolidating the majority of them into one sector, it will get a lot more attention."

Indexes including the S&P 500 are a guide for trillions of dollars of capital worldwide, including index-tracking, exchange-traded funds (ETFs) that target specific sectors.

"This is a huge deal," said Todd Rosenbluth, director of ETF and mutual fund research at CFRA. "Where a stock ends up and who it's compared to can impact where money goes within capital markets."

(Reporting by Dan Burns, Trevor Hunnicutt, Rodrigo Campos and Caroline Valetkevitch in New York; editing by Sandra Maler, Tom Brown and G Crosse)

By Trevor Hunnicutt and Rodrigo Campos