David Tepper's Appaloosa Management disclosed a $7.7 billion portfolio in its latest 13F filing with $3.1 billion — 40% of assets under management — concentrated in three names: Amazon, Micron Technology, and Taiwan Semiconductor Manufacturing. The position sizes matter more than the thesis. Tepper runs a hedge fund, not an index.
The Micron holding is the unusual data point. Tepper sold 41% of his Micron stake during a quarter in which the stock climbed 242%. The stock is still his second-largest position. That combination — trimming into a rally while keeping the name at scale — suggests conviction in the three-year semiconductor buildout cycle rather than momentum capture. Amazon remains the largest holding. Taiwan Semiconductor rounds out the trio. All three names sit at different points in the AI supply chain: hyperscale cloud capital expenditure, memory and compute hardware, and foundry fabrication.
The concentration itself is the forward guidance. Appaloosa historically runs a more distributed book across technology, healthcare, and financials. A 40% weight in three correlated positions represents a deliberate reduction in surface area. Tepper is not hedging the semiconductor thesis. He is sizing it. The Amazon position captures the capital-expenditure side — the company guided to $105 billion in capex for 2025, most of it earmarked for AI infrastructure. Micron plays memory bandwidth constraints in high-performance compute clusters. Taiwan Semiconductor controls the fabrication bottleneck for cutting-edge logic chips. The three names form a stack, not a basket.
The portfolio construction tells allocators where Tepper sees the next twelve months of multiple expansion. He is underweight software multiples and overweight capital-intensive hardware with pricing power. That positioning works if enterprise AI spending accelerates in the back half of 2025 and hyperscalers continue bidding up chip supply. It breaks if cloud capex guidance disappoints or if memory prices revert after the current supply tightness resolves. The Micron trim during a 242% run suggests Tepper is managing position size risk, not exiting the trade. The fact that he kept it as the number-two holding after a 41% reduction means the original stake was materially larger. He sold into strength and still owns scale.
Allocators should watch three specific events. First, Amazon's Q1 earnings in late April will include updated capex guidance for the year. Any revision below $100 billion would force a reassessment of hyperscaler demand. Second, Micron reports fiscal Q2 earnings in late March. The guidance on high-bandwidth memory pricing will clarify whether supply tightness persists into the second half of the year. Third, Taiwan Semiconductor's April revenue report will show whether 3-nanometer chip demand from Nvidia and AMD remains above foundry capacity. All three reports land within a six-week window.
Tepper filed the 13F on February 14, 2025, reflecting positions as of December 31, 2024. The portfolio has had six weeks to drift. The filing shows conviction at year-end, not current exposure.