WASHINGTON, Nov 21 (Reuters) - U.S. Securities and

Exchange Commission Chair Gary Gensler will step down on Jan. 20

when President-elect Donald Trump's administration takes over,

the agency said on Thursday, ending an ambitious tenure that saw

him clash with Wall Street and the crypto industry.

"I thank President Biden for entrusting me with this

incredible responsibility. The SEC has met our mission and

enforced the law without fear or favor," Gensler, who was

nominated by Democratic President Joe Biden in 2021, said in a

statement.

Known for his hard-charging style, Gensler led an

ambitious agenda to boost transparency, reduce systemic risks,

and stamp out conflicts of interest on Wall Street, completing

dozens of new rules, some of which have been challenged in

court.

Among his major accomplishments were changes to boost the

resilience and efficiency of U.S. markets, including speeding up

trade settlements and overhauling the $28 trillion Treasuries

market, as well as a number of rules boosting investor

disclosures and corporate governance.

The Baltimore native also successfully implemented rules

mandated by Congress imposing SEC oversight on auditors of

U.S.-listed Chinese companies, ending a decade-long tussle with

Beijing that lawmakers said had put U.S. investors at risk.

On the enforcement front, Gensler's SEC broke new ground

with a multi-year effort focused on Wall Street's use of text,

WhatsApp and other unauthorized channels to discuss business,

levying more than $2 billion in fines against dozens of firms,

including JP Morgan and Goldman Sachs ( GS ).

He also took on the crypto industry, suing Coinbase

, Kraken, Binance and others, alleging that their

failure to register with the agency violated SEC rules,

accusations the companies deny and are fighting in court. When

it comes to crypto, the courts have mostly backed Gensler's

positions.

But his sweeping agenda and uncompromising posture sparked

intense pushback from Wall Street, as well as congressional

Republicans, and even some Democrats.

The U.S. Chamber of Commerce, Managed Funds Association and

other groups sued in the conservative-leaning Fifth U.S. Circuit

Court of Appeals and elsewhere to overturn at least eight rules,

arguing they were unjustified, harmful or beyond the SEC's

authority.

(Writing by Michelle Price; Additional reporting by Chris

Prentice in New York; Editing by Paul Simao)