David Tepper's Appaloosa Management disclosed a $7.7 billion equity portfolio with 40%—roughly $3.1 billion—concentrated in three names: Amazon, Micron Technology, and Taiwan Semiconductor Manufacturing. The 13F filing, covering positions as of December 31, reveals Tepper sold 41% of his Micron stake during the quarter yet kept enough to make it his second-largest holding. Micron rose 242% in the prior twelve months. He sold into strength and still maintained conviction.
The allocation is structural, not speculative. Amazon sits atop the portfolio, likely weighted toward AWS infrastructure spend. Micron and TSM supply the memory and fabrication layer underneath every frontier model deployment. Tepper is not betting on narrative; he is betting on the supply chain chokepoints that hyperscalers cannot route around. The trim in Micron suggests position management after a parabolic move, not thesis abandonment. When a manager sells 41% of a position and it remains the second-largest line, the original sizing was deliberate overweight.
This matters because Appaloosa runs concentrated capital, not indexed beta. Tepper historically runs 12 to 18 core positions. A 40% weight in three names is distribution risk taken with eyes open. The downstream implication: he expects these three to outperform the index by enough margin to justify the tracking error. For allocators, this is a signal about where institutional capital sees the next 18 to 24 months of margin expansion. AWS capex, HBM pricing power, and leading-edge node allocation are the variables Tepper is long. The trimming behavior—taking profit in Micron while holding Amazon and TSM flat—suggests he sees memory as more cyclical than compute or fabrication capacity.
Operators should watch Micron's March quarter earnings for commentary on HBM3E contract visibility and TSM's April revenue disclosure for N3 wafer starts. Amazon reports February 6; any AWS growth deceleration below 17% year-over-year would pressure the thesis. Appaloosa typically files amendments within 45 days if position sizes move more than 5%, so mid-February to early March is the window for follow-on disclosure. If Tepper adds to TSM or trims Amazon, that is the tell.
The filing does not disclose derivatives or non-US listings, which means the actual exposure to semiconductor infrastructure could be higher. Tepper runs a global book. The visible equity slice is the floor, not the ceiling.