The London Stock Exchange has been experiencing outages. Photo: Toby Melville/Reuters (Toby Melville / reuters)

The London Stock Exchange (LSEG.L) faced an outage on Tuesday morning, hitting trading in hundreds of small cap stocks.

It was the third trading outage in two months, with FTSE 100 (^FTSE) and 250 (^FTMC) stocks unaffected by the halt.

Trading was suspended in about 2200 smaller shares, including online retailer Asos (ASC.L), drinks maker Fevertree (FEVR.L) and polling company YouGov (YOU.L). Online food delivery company Deliveroo (ROO.L) was also unable to trade on Tuesday morning.

The exchange said: "The London Stock Exchange is still investigating an incident.

Read more: LIVE: FTSE and European stocks muted as UK grocery inflation slows

"We are undertaking immediate analysis and will provide further updates through our live service portal.

"Currently only FTSE 100, FTSE 250 and IOB securities are available for trading."

Shortly after 10am, London Stock Exchange Group (LSEG) said in a notice that trading across all its markets had resumed. It did not disclose the cause of the issue.

London Stock Exchange Is Hit By Third Outage Since October pic.twitter.com/7AerZwb5Wk

— Baron Investments (@baroninvestment) December 5, 2023

In October, the exchange was hit by a roughly 80-minute outage which halted trading for hundreds of smaller stocks, with FTSE 100 and FTSE 250 shares once again unaffected. In November, FTSE Russell indices also faced a trading glitch.

Read more: Trending tickers: GameStop | Nvidia | Ericsson | Barclays

In 2019, the London Stock Exchange suffered an almost two-hour outage that hit FTSE 100 and midcap stocks, which LSEG said was caused by a “technical software issue”.

The recent outages come as LSEG is seeking to transform itself from an exchange provider into a data services provider.

Watch:Stocks tend to rise in December, will this year differ?Jared Blikre breaks down stocks and looks closely at sectors that will most likely thrive during this season— and what this could signal for early 2024.
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Blikre notes that the period between Thanksgiving and Black Monday leading up to the Christmas holidays and end of the calendar year are generally positive for stocks. with \"historically bullish signals.\" 
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The question is whether we will follow that trend this year. So far, things are looking good, with communications services, consumer discretionary, financials, healthcare and energy, all moving higher, with more gains to potentially come. On the flip side: technology and real estate - two sectors that have faced challenges of late, and are interest rate-sensitive.
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With softening economic growth and expectations of the Federal Reserve at minimum keeping benchmark interest rates on hold, the possibility of an overall positive end to the year for stocks is looking increasingly likely. At the same time, economists and strategists are divided on whether that will continue into 2024.  
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