NEW YORK (Reuters) - At least three new U.S. stock exchanges are expected in 2020, executives from the companies said on Thursday, potentially lowering trading costs as the upstarts try to take business from the incumbents, while also adding complexity to the marketplace.

FILE PHOTO: Traders work on the floor at the New York Stock Exchange (NYSE) in New York, U.S., September 9, 2019. REUTERS/Brendan McDermid

There are currently 13 U.S. stock exchanges, 12 of which are run by Intercontinental Exchange Inc's ICE.N NYSE, Nasdaq Inc NDAQ.O, and Cboe Global Markets CBOE.Z. IEX Group runs the only independent exchange.

“I could see us getting to 20-plus,” Bryan Harkins, co-head of markets at Cboe, said of the potential for new exchanges, at a Securities Industry and Financial Markets Association conference.

Next year, launches are planned for the Members Exchange, a new bourse backed by a group of large financial firms; a stock exchange run by options exchange operator Miami International Holdings that says it will eventually list companies from Latin America; and the Long Term Stock Exchange, a Silicon Valley-based startup aimed at promoting long-term growth ahead of short-term profits for the companies it lists.

The increased competition comes as NYSE, Nasdaq and Cboe sue the U.S. Securities and Exchange Commission to prevent an experiment mandated by the regulator to test lowering exchange fees and curtailing payments to brokers for orders.

It also comes amid an intense debate between the large exchange operators and their customers over fees for things like market data and connectivity.

“We’re going to start out 40 percent cheaper than the lowest cost operator today,” said Thomas Gallagher, chief executive officer of Miami International Holdings. He said his exchange will launch in the second or third quarter next year.

The Members Exchange, which aims to go live in mid-2020 and is backed by financial heavyweights including Virtu Financial Inc VIRT.O, Morgan Stanley MS.N and TD Ameritrade AMTD.O, will also have lower fees while also giving its members a bigger voice in the fee debate, said CEO Jonathan Kellner.

LTSE CEO Zoran Perkov said his exchange will launch “soon.”

New exchanges can add value to the market, but also add complexity and may make illiquid stocks harder to trade, said Tal Cohen, head of Nasdaq’s North American market services.

MIAX’s Gallagher pointed to his firm’s success in the options market, where it has gained around 10% market share, opening three options exchanges in less than seven years.

“When you make a movie that does well, you do it again and you do it again and you do it again,” he said.