LONDON/NEW YORK (Reuters) -Trading in commodities, stocks, currencies and bonds returned to normal on Friday after a global cyber outage hampered operations at financial services firms from London to Singapore and New York, although residual problems remained.

A software update by global cybersecurity firm CrowdStrike wreaked havoc on computer systems globally, grounding flights, forcing some broadcasters off air and hitting services from banking to healthcare.

The outage sent ripples through financial markets during Asia and early European trading hours, with a number of firms involved in various aspects of the trading process affected.

Due to the outage “certain online functionality may be intermittently slow or unavailable,” major U.S. brokerage Charles Schwab said on its website. “Phone services may be disrupted and hold times may be longer than usual.”

An options trader and Schwab customer, who requested anonymity to discuss business relationships, said that their firm had trouble getting information on client trades sent through Schwab.

“We are single-mindedly focused on our clients’ experience and are communicating with them directly about this unprecedented, global and industry-wide situation,” a Schwab spokesperson told Reuters on Friday afternoon.

LSEG Group, which runs the London Stock Exchange, said its Workspace news and data platform, regulatory news service and currency spot and forward prices had been affected by the outage. By midday in London, most of those issues seemed to have been resolved and securities trading on the London Stock Exchange was not affected.

A spokesperson for FTSE Russell, which is part of LSEG, said that the index provider had experienced problems that prevented “clients from accessing and receiving data” and which affected its indices.

The European Energy Exchange said in a statement that clients using the Trayport power and gas trading platform were having problems trading “due to infrastructure issues with third-party service provider”.

At least six trading sources at oil majors Shell and BP, as well as trading house Vitol, said operations were affected. BP and Shell did not immediately respond to requests for comments.

Vitol said core trading operations were functioning well though some individual computers and some processes that interface with third party systems were impacted temporarily.

“Friday’s global tech outage is an example of an unforeseen event that market participants always fear, but don’t frequently think about,” said Glen Smith, chief investment officer at GDS Wealth Management.

New York’s state regulator, which oversees more than 3,000 financial institutions, warned firms to remain vigilant, as bad actors “have been known to launch attacks during periods when IT and security staff are distracted.”

By Friday afternoon in U.S. hours, though, it was mostly business as usual.

The New York Stock Exchange and Nasdaq said markets were working normally. Major energy traders and exchanges, including the Intercontinental Exchange, which owns NYSE, and CME Group said they had not experienced issues as of midday Friday.

The Commodity Futures Trading Commission, which oversees commodity derivative markets, said it was seeing sporadic outages among users but most were not impacted and weekly traders’ data would be published on Friday as usual.

Major U.S. banks including Bank of America and Goldman Sachs said they had not seen any major impact on their systems or operations. Citigroup has also not been affected, a source familiar with the matter said.

HURDLES TO ACCESSING SYSTEMS

While there were no confirmed reports of major trading glitches, some traders earlier said there were signs of disruption at smaller financial institutions. One London-based trader said several trading platforms were affected, leaving some clients unable to trade.

Some banks and financial services firms said employees and customers had problems accessing their systems.

“People can’t switch their computers on after restarts. Those who didn’t restart are doing fine,” another trader said.

Barclays reported customers were unable to manage accounts on its digital investing platform Smart Investor. Germany’s Allianz said the outage affected the ability of employees to log on to their computers. Banks in South Africa also reported disruptions.

A spokesperson at the Financial Services Information Sharing and Analysis Center (FS-ISAC), the global cyber intelligence group, said the outages had not had a systemic impact on the financial services industry.

“Core functions, including banking and payment processing, are largely functioning with some scattered effects,” the spokesperson said.

Monsur Hussain, Head of Financial Institutions Research at Fitch, said the outage would likely increase regulatory scrutiny of financial firms’ use of third-party IT providers.

“The economies of scale are compelling, but they can also bring systemic risks,” he said.

(Reporting by Karin Strohecker, Sinead Cruise, Ron Busso, Susanna Twidale and Dmitry Zhdannikov in London; Saeed Azhar, Tatiana Bautzer, Carolina Mandl, Laura Matthews, Saqib Iqbal Ahmed, Michelle Price; Tom Polansek, PJ Huffstutter, Renee Hickman, Arathy Somasekhar and Marianna Parraga; Writing by Dmitry Zhdannikov and Karin Strohecker; Editing by Arun Koyyur, Megan Davies, Kirsten Donovan and Diane Craft)

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