Shell (SHEL.L)

Oil major Shell warned that third-quarter refining profit margins were set to be much lower than the previous quarter, in an update note published on Monday ahead of results due to be released on 31 October.

Shell said it expected indicative refining margins of $5.50 (£4.19) a barrel for the three months to the end of September, down from $7.70 a barrel in the previous quarter.

This comes amid a slowdown in oil demand, with economic headwinds in major economies such as China, seen as a contributor. The Organization of the Petroleum Exporting Countries (OPEC) lowered its demand growth forecast for 2024 and 2025 last month.

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However, oil prices have surged recently, amid escalating conflict in the Middle East and concerns about what this could mean for supply in the market. Brent crude futures (BZ=F) were up 0.74% to $78.63 a barrel on Monday morning, as traders await Israel’s response to Iran’s missile barrage last week amid ongoing fears about a region-wide war in the Middle East.

In Monday's trading note, Shell lifted its guidance for liquified natural gas for the third quarter to between 7.3 million and 7.7 million metric tons, from a previous forecast of 6.8 million to 7.4 million.

Susannah Streeter, head of money and markets at Hargreaves Lansdown, said: "Energy giants have been making gains over the past week, as oil prices have headed higher. However, Shell’s update this morning has indicated that it’s not been firing on all cylinders."

Shell shares were little changed on Monday morning.

BP (BP.L)

Another oil major in focus, following reports that BP had dropped its target to reduce oil and gas output by 2030.

Reuters reported that the company had abandoned its plans as CEO Murray Auchincloss looks to regain investor confidence.

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BP had already scaled back its plans to cut oil and gas production last year, when it said it would look to reduce output by 20% to 30% by 2030, rather than the previous target of 35% to 40%.

A spokesperson for BP said: "As Murray said at the start of year in our fourth quarter results, the direction is the same — but we are going to deliver as a simpler, more focused, and higher value company."

Shares in BP saw little movement on the back of the news on Monday morning.

Pfizer (PFE)

Shares in Pfizer were up more than 2% in pre-market trading on Monday morning, on the back of reports that activist investor Starboard Value had taken a stake of around $1bn in the US pharmaceuticals company.

The Wall Street Journal reported on Sunday that Starboard took a stake as it looked for Pfizer to make changes to turn its performance around.

Pfizer shares have been under pressure this year, with the stock nearly 1% in the red year-to-date.

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In January, it reported a revenue slump in the fourth quarter tied to a slowdown in demand for its Covid-19 vaccine.

However, the company reported in July second-quarter revenue and earnings that beat expectations and lifted its outlook for the full-year. Pfizer said it expected revenues to range between $59.5bn and $62.5bn for the full year 2024, up from previous guidance of $58.5bn to $61.5bn.

Neither Pfizer nor Starboard Value had responded to Yahoo Finance UK's request for comment at the time of writing.

Rio Tinto (RIO.L)

Miner Rio Tinto confirmed on Monday that it had approached Arcandium Lithium to buy the company, which is worth $3.3bn.

Rio Tinto said the approach was "non-binding and there is no certainty that any transaction will be agreed to or will proceed" but offered no further details on the potential deal.

Shares in the miner were flat on Monday morning, while US-listed Arcadium Lithium (ALTM) surged nearly 28% in pre-market trading.

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Russ Mould, investment director at AJ Bell, said: "Rio Tinto appears to have learned from its mistakes in the commodities boom a decade ago where it overpaid for assets at the top of the market.

"The lithium market has been going through a bad patch of late, depressed by Chinese oversupply and weak demand for the battery material as the adoption of electric vehicles has been slower than expected.

"That’s depressed shares in Arcadium and created an opportunity for Rio to pounce while the target is down on its luck."

Mould explained that Rio Tinto would likely want to beat rivals and and "become one of the world’s key sources of lithium so as to capitalise on the structural shift to electric vehicles and ongoing demand for consumer electronics. That means securing the best assets now before the market improves.”

Semiconductor Manufacturing International Corporation (0981.HK)

Shares in Semiconductor Manufacturing International Corporation (SMIC) surged 22% in Monday's session, as the Hong Kong-listed chipmaker was buoyed by continued enthusiasm of recently announced Chinese stimulus measures.

Bloomberg reported that SMIC led a rally in its sector on Monday, seeing Chinese chip stocks gain $13bn.

Hua Hong Semiconductor Limited (1347.HK) and Shanghai Fudan Microelectronics Group Co. (1385.HK) were other stocks in the sector that also gained, up 16% and 21% respectively.

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Investors will be looking ahead to a press briefing on Tuesday with China's top economic policymakers, as mainland markets re-open following the week-long Golden Week holiday.

There is set to be a briefing at with officials from China's National Development and Reform Commission on Tuesday, which investors will investors will be keeping an eye on for any further economic stimulus measures.

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