Rather like some World Cup matches, 1H 2026 was a tale of two halves for global stocks, minus the hydration breaks. Q1 saw stocks struggle on the Iran conflict, while Q2 saw them rally on blowout US earnings.
Unsurprisingly, due to the weight of Tech stocks in the indices, US stocks fared better than UK stocks. For 1H 2026 the S&P 500 notched up a 10% gain and the Nasdaq 100 posted a 19% gain. In contrast, large-cap UK stocks ended 1H with a gain of 5% while unusually mid-caps underperformed with just a 3% gain.
Channelling Bloomberg columnist John Authers’ imaginary hedge fund ‘Hindsight Capital’, we’ve analysed the best and worst trades of 2026 so far. While Tech dominated the winners, it certainly wasn’t a one-way trade.
As Authers explains: ‘The biggest gains have gone to those who poured into chip stocks while shorting software. This was on the basis AI would create ever greater demand for semiconductors while destroying the business model for software groups.’
Over the last six months, shorting software stocks and buying the SOX semiconductor index would have returned 150%, adds Authers. Meanwhile, although the UK market lacks much exposure to chips, it does have its share of potential AI losers.
US 1H winners and losers
By any measure, the 1H gains posted by some Technology stocks were unusually strong and reflect frenzied buying by retail investors. Also, with passive funds and ETFs having to chase stocks higher, price discovery seems to have gone out the window.
S&P 500 1H winners
| Stock | Sector | Gain |
| SanDisk | Technology | 847% |
| Micron | Technology | 294% |
| Intel | Technology | 274% |
| Western Digital | Technology | 263% |
| Seagate | Technology | 245% |
| Marvell | Technology | 243% |
| Dell | Technology | 237% |
| Corning | Technology | 187% |
| Applied Materials | Technology | 178% |
| AMD | Technology | 170% |
Source: Stockopedia
Due to the way the indices are compiled, the top performers in the Nasdaq 100 are mostly the same stocks. However, UK investors will no doubt recall Arm Holdings (NASDAQ:ARM) and rue what might have been.
Nasdaq 100 1H winners
| Stock | Sector | Gain |
| SanDisk | Technology | 847% |
| Micron | Technology | 294% |
| Intel | Technology | 274% |
| Western Digital | Technology | 263% |
| Seagate | Technology | 245% |
| Marvell | Technology | 243% |
| Nebius | Technology | 224% |
| Arm Holdings | Technology | 220% |
| Astera Labs | Technology | 183% |
| Applied Materials | Technology | 178% |
Source: Stockopedia
As flagged above, Technology was far from a one-way bet as investors sold stocks they thought would lose out to AI. Those centred on companies selling business process software and data providers, although one or two Health Care companies also appear on the lists.
S&P 500 1H losers
| Stock | Sector | Loss |
| Leidos | Technology | -44% |
| Lululemon | Consumer Cyclicals | -46% |
| Insulet | Health Care | -47% |
| Gartner | Technology | -49% |
| TradeDesk | Technology | -53% |
| Accenture | Technology | -54% |
| Cognizant | Technology | -54% |
| Boston Scientific | Health Care | -56% |
| CoStar | Technology | -58% |
| Intuit | Financials | -61% |
Source: Stockopedia
Nasdaq 100 1H losers
| Stock | Sector | Loss |
| Constellation Energy | Utilities | -31% |
| Intuitive Surgical | Health Care | -31% |
| PDD | Technology | -33% |
| Autodesk | Technology | -35% |
| Palantir | Technology | -36% |
| Thomson Reuters | Industrials | -39% |
| Adobe | Technology | -42% |
| Workday | Technology | -44% |
| Strategy | Technology | -44% |
| Intuit | Financials | -61% |
Source: Stockopedia
UK winners and losers
Among large-cap UK stocks, Technology in general was represented by Polar Capital Technology (LON:PCT) investment trust and Computacenter (LON:CCC). Financial stocks were also gainers, and not only bid targets like Beazley (LON:BEZ) and Schroders (LON:SDR). Finally, Industrials made the grade thanks to compounders DCC (LON:DCC) and Diploma (LON:DPLM).
UK large-cap 1H 2026 winners
| Stock | Sector | Gain |
| Polar Cap Technology | Financials | 54% |
| Beazley | Financials | 53% |
| Computacenter | Technology | 44% |
| Schroders | Financials | 43% |
| IG Group | Financials | 38% |
| DCC | Industrials | 34% |
| Diploma | Industrials | 33% |
| Hiscox | Financials | 29% |
| Coca-Cola Hellenic | Staples | 28% |
| Glencore | Basic Materials | 26% |
Source: Stockopedia
The losers also contained a mix of Technology, Financials and Industrials, with a sprinkling of Consumer Cyclicals. ‘AI losers’ included credit rating firm Experian (LON:EXPN), media group RELX (LON:REL) and accounting software seller Sage (LON:SGE).
UK large-cap 1H 2026 losers
| Stock | Sector | Loss |
| Fresnillo | Basic Materials | -20% |
| Pershing Square | Financials | -22% |
| RELX | Technology | -22% |
| Persimmon | Consumer Cyclicals | -23% |
| Babcock | Industrials | -23% |
| 3i Group | Financials | -23% |
| Sage | Technology | -25% |
| Experian | Industrials | -25% |
| Barratt Redrow | Consumer Cyclicals | -26% |
| Entain | Consumer Cyclicals | -27% |
Source: Stockopedia
Housebuilders Barratt Redrow (LON:BTRW) and Persimmon (LON:PSN) remained a poor bet, consistent with our thinking. However, names like 3i Group (LON:III) and Pershing Square (LON:PSH) were certainly not on our score card back in January.
Mid-cap winners and losers
The trends in large-caps permeated the mid-cap market, as expected, where pc maker Raspberry Pi (LON:RPI) was the standout winner. Also sporting triple-digit gains was XP Power (LOM:XPP), which makes power converters, part of the essential kit for for running data centres.
UK mid-cap winners
| Stock | Sector | Gain |
| Raspberry Pi | Technology | 172% |
| Ceres Power | Energy | 137% |
| XP Power | Industrials | 116% |
| Saga | Financials | 62% |
| Keller | Industrials | 59% |
| Seraphim | Financials | 56% |
| Trustpilot | Technology | 56% |
| CMC Markets | Financials | 55% |
| Pacific Horizon | Financials | 51% |
| Senior | Industrials | 49% |
Source: Stockopedia
Given the excitement around the SpaceX IPO, it’s no surprise Seraphim Space Investment Trust (SSIT) made the list. More surprising were large gains for infrastructure group Keller (LON:KLR), investment trust Pacific Horizon (LON:PHI) and cruise and insurance seller Saga (LON:SAGA).
UK mid-cap losers
| Stock | Sector | Loss |
| GlobalData | Industrials | -33% |
| ME Group | Industrials | -34% |
| Shawbrook | Financials | -34% |
| THG | Technology | -35% |
| WH Smith | Consumer Cyclicals | -39% |
| Aston Martin Lagonda | Consumer Cyclicals | -41% |
| Hays | Industrials | -44% |
| Telecom Plus | Utilities | -46% |
| Page Group | Industrials | -55% |
| Vistry | Consumer Cyclicals | -60% |
Source: Stockopedia
Just as the 1H mid-cap winners more or less resembled the large-cap winners, the same was true of the mid-cap losers. Businesses seen as casualties of AI adoption – such as staffers Hays (LON:HAS) and PageGroup (LON:PAGE) – were hit hard, as were housebuilders.
Meanwhile, some firms just couldn’t stay out of trouble – serial disappointer Aston Martin Lagonda (LON:AML) being a case in point. Finally, former market darlings ME Group (LON:MEGP) and Telecom Plus (LON:TEP) fell from grace after disappointing investors with their outlooks.
