NEW YORK, April 30 (Reuters) - Citadel Securities has

sent the U.S. Securities and Exchange Commission a wish list for

capital markets regulation, including warnings about the risks

of 24-hour trading planned by exchanges.

The market maker founded by billionaire investor Ken Griffin

said overnight trading requires a clear regulatory framework, as

well as market infrastructure to support it, calling for

consistency around dates.

Exchanges like Nasdaq, Cboe Global Markets ( CBOE )

and Intercontinental Exchange ( ICE ), the operator of the New

York Stock Exchange, have announced plans for extended trading

hours.

The 29-page letter, which became public on Wednesday, also

contains proposals for equities, derivatives, treasuries, credit

and digital assets. It includes requests for new regulation, as

well as for the revision of some rules. The firm trades roughly

$570 billion a day, according to its website.

The SEC did not immediately comment on Citadel's capital

markets proposals.

The lengthy list called for more regulation of so-called

private rooms, or alternative trading systems in which the

number of market participants is limited.

"These private rooms raise a number of concerns that warrant

regulatory scrutiny," the firm said in the letter, adding that

they do not comply with fair access and transparency rules.

In the fixed income market, Citadel favors more transparency

in the corporate bond market, calling for a faster disclosure of

block trade sizes.

Citadel's wish list comes as Paul Atkins, who previously

served as an SEC member from 2002 to 2008 and was seen as a

business-friendly lawyer, was sworn as the regulator's chairman

earlier this month.