Shares linked to artificial intelligence, cryptoassets and space communications dominated buying activity among Robinhood UK customers in December 2025, according to trading data that highlights how retail investor attention is coalescing around a small number of powerful technology themes.
The most actively bought stocks by total value of buy trades included Marathon Digital Holdings, Nvidia, Oracle, Robinhood Markets, Tesla, IREN, Coinbase, Nebius, Amazon and AST SpaceMobile.
All are constituents of either the S&P 1500 or the Nasdaq Composite and maintained an average market capitalisation of at least $1bn throughout the month.
Dan Lane, investment content lead at Robinhood UK, said December’s activity reflected continued interest in what he described as “space communications technology, AI infrastructure and crypto” as overlapping investment narratives.
“If 2025 was the hyperscalers’ year, will 2026 be all about AI infrastructure?” he said.
Bitcoin miner Marathon Digital Holdings remained among the most popular names despite a weak end to the year for the stock. Lane said a bearish turn in crypto markets weighed on performance in December but noted that investor interest had not faded.
“It was a tough end to the year for MARA, but it looks like investors are still keen on the Bitcoin-miner-to-AI-infrastructure narrative at play,” he said. A similar dynamic applied to IREN, with investors assessing the balance between its data-centre business and its crypto-mining revenues.
Nvidia, the leading supplier of high-performance chips for artificial intelligence workloads, rose towards the end of the month as expectations grew around plans to ship its H200 chips to China early in the new year.
Lane said uncertainty remained over regulatory approval in Beijing, alongside rising geopolitical tensions and a push for domestic technology solutions.
Although Nvidia’s newer Blackwell chip offers higher performance, investors appeared to be “banking on enough appetite from Chinese firms to make a hopeful deal meaningful to revenues”.
Oracle climbed to third place in December’s rankings as buyers moved in after a share price dip. While the company has reported revenue growth and what Lane described as “a seemingly robust pipeline”, investor caution reflected the scale of spending required to build AI capacity and a reported $108 billion debt pile.
“The fact that it’s taking a while to translate into clear profits added to market worries,” he said.
Tesla rose to fifth place despite continued weakness in Europe. According to figures from the European Automobile Manufacturers Association, registrations fell 34.2% year on year in November, cutting market share as Chinese rival BYD expanded sales across the EU, the European Free Trade Association and the UK.
Crypto exchange Coinbase slipped further in December after peaking earlier in the year, as volatility in digital-asset markets continued to weigh on the stock despite product expansion plans.
Nebius, an AI cloud infrastructure group, remained popular but fell down the rankings following a volatile month, even as it raised guidance and reported selling all available computing capacity in the third quarter.
Amazon ended December broadly flat, with buying activity focused on the long-term growth of Amazon Web Services and new tools announced to help customers build AI agents.
AST SpaceMobile joined the list after a strong month, following the successful launch of its BlueBird 6 satellite, which acts as a mobile phone tower in space.