What Super Investors Are Buying: 13F Filings Decoded

Why 13F Filings Are the Closest Thing to a Cheat Sheet in Investing

Every quarter, investment managers overseeing more than $100 million in assets are legally required to file a 13F disclosure with the SEC — a document that lists their US equity holdings as of the last day of the quarter. Most retail investors scroll past these filings without a second glance. That is a mistake.

The latest round of 13F filings delivered some of the most significant portfolio moves seen in years from marquee names including Berkshire Hathaway, Pershing Square, and Baupost Group. Taken together, they paint a coherent picture: the world's most disciplined value investors are not sitting on the sidelines. They are selectively deploying capital into high-quality technology businesses that experienced sharp, sentiment-driven sell-offs — while simultaneously pruning legacy positions and tidying up portfolios under new leadership.

Here is a breakdown of the key moves, what the data says, and what serious investors can take away from it.

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Berkshire Hathaway Triples Down on Google — and Culls 16 Positions

The headline move from Berkshire Hathaway was a tripling of their position in Alphabet Class A shares, paired with a fresh $1 billion allocation into Class C shares. The Class A stake alone is now worth approximately $15.6 billion, making Alphabet Berkshire's seventh-largest equity position.

The immediate question raised in markets: was this Warren Buffett or Greg Abel?

Buffett stepped down as CEO but retains oversight of major equity decisions. However, he has consistently acknowledged that large-cap technology companies sit outside his defined circle of competence. Greg Abel, his designated successor, has been operationally in charge and the timing — his first full quarter running the portfolio — makes Abel a credible architect of this trade.

The investment rationale, regardless of who pulled the trigger, is straightforward on fundamentals:

• Revenue and earnings growth: Alphabet has delivered compounding revenue and earnings growth with no meaningful deceleration in recent reporting periods.
• Balance sheet strength: The company holds substantially more cash than total debt — a profile that mirrors Berkshire's own financial conservatism.
• Free cash flow generation: Alphabet remains one of the most cash-generative businesses on earth, with its advertising and cloud segments providing durable, recurring income streams.
• AI positioning: Unlike pure-play AI startups, Alphabet is competing directly with its own Gemini models while maintaining its dominant search infrastructure. It is better capitalised than OpenAI and operationally embedded in enterprise workflows.

Valuation is the honest caveat here. At a price-to-earnings ratio of approximately 30 and a modest premium to discounted cash flow estimates, Alphabet is not cheap by any absolute measure. But Buffett's own framework — a wonderful company at a fair price beats a fair company at a wonderful price — applies cleanly. At scale, Berkshire cannot simply wait for a 15-forward-PE entry point that may never arrive.

The more structurally significant move, however, was not the Google buy. It was the complete liquidation of 16 positions in a single quarter — a cull of a scale rarely seen in Berkshire's history. Many of the exited names appear to be associated with Todd Combs, one of Berkshire's former portfolio managers who recently departed to join JPMorgan. Positions in Visa, Mastercard, Domino's, and Amazon were among those sold entirely. The largest single impact was Visa, which represented roughly 1% of the total portfolio — meaning no individual exit was seismic, but the collective signal is hard to ignore.

The most plausible interpretation: Greg Abel is establishing his own investment identity at Berkshire, shedding smaller satellite positions that don't fit his framework and consolidating capital into larger, higher-conviction bets.

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Bill Ackman Opens a $2 Billion Microsoft Position While Others Flee

Pershing Square's Bill Ackman spent Q1 doing something most institutional investors were not: buying Microsoft as the stock slid nearly 25% from its peak.

Ackman opened a $2 billion position, immediately ranking it as the fourth-largest holding in Pershing Square's US portfolio. The context matters enormously here. Microsoft's share price declined sharply as investors grew increasingly anxious about the company's capital expenditure commitments to AI infrastructure — data centres, GPU procurement, power systems, and network buildout. Free cash flow, a metric many investors rely on as a proxy for business health, appeared to stall under the weight of this spending.

But Ackman's counter-argument — articulated publicly at investment conferences — is that elevated CapEx driven by a deliberate strategic choice is categorically different from elevated CapEx caused by operational deterioration. Microsoft is not bleeding cash because its business is broken. It is choosing to invest aggressively in infrastructure it believes will generate outsized returns. That distinction matters.

On a price-to-earnings basis, Microsoft at approximately 25x earnings trades at a meaningful discount to most of its Magnificent Seven peers, many of which carry PE ratios in the 30s, 40s, and beyond. Discounted cash flow models that account for normalised CapEx levels suggest meaningful undervaluation relative to intrinsic value.

Key takeaway for investors: fear-driven selling in structurally sound businesses creates the entry points that patient capital exploits. Ackman's Microsoft trade is a textbook example of that dynamic.

In a notable contrast, Ackman simultaneously sold out of his Google position — essentially rotating from one mega-cap technology holding into another, but at what he assessed as a more compelling risk-adjusted price point. He also added approximately 20% to his Amazon position, which now ranks as Pershing Square's second-largest holding.

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Seth Klarman Increases Amazon by 47% — and the Timing Was Near-Perfect

Seth Klarman, the author of Margin of Safety and one of the most respected value investors alive, increased Baupost's Amazon position by 47%. Amazon now constitutes 12.7% of Baupost's US portfolio — the single largest position in the fund.

The timing aligns directly with a sharp, short-lived sell-off in Amazon's share price. In early February, Amazon released Q4 earnings that included guidance of approximately $200 billion in capital expenditures for the following year, the majority directed at AI infrastructure, AWS expansion, chip procurement, and data centre capacity. The market's response was immediate and severe: the stock fell roughly 18% in approximately one week.

To put that in perspective, the market temporarily concluded that Amazon's entire business was worth nearly a fifth less than it had been seven days earlier — based on a voluntary decision by management to invest more aggressively in growth.

The rebuttal to that logic is simple but important:

• Voluntary CapEx is reversible. If demand signals weaken, Amazon can throttle spending. This is not a structural impairment.
• Revenue and earnings trends remained positive. The underlying business did not deteriorate — management chose to allocate more capital to infrastructure with long-term return potential.
• AWS was subsequently reported as supply-constrained, not demand-constrained — meaning the company was turning away business due to infrastructure limitations, not struggling to find customers. That is a fundamentally different problem.

When the Q1 follow-up earnings confirmed stronger-than-expected AWS growth and management reaffirmed the demand outlook, the stock recovered sharply. Klarman's incremental position, built during the panic, benefited substantially.

This is what margin-of-safety investing looks like in practice: not buying distressed businesses at low prices, but buying exceptional businesses at temporarily irrational prices.

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Other Notable 13F Moves Worth Watching

Beyond the three headline stories, several secondary moves from the latest filings deserve attention:

• Berkshire adds $2.6 billion in Delta Air Lines: Buffett famously lost money on airlines during the COVID-19 pandemic, selling the entire sector at a loss in 2020. This re-entry — or Abel's entry — into Delta suggests renewed conviction in the airline's competitive position, operational recovery, and loyalty economics. Delta has consistently demonstrated stronger pricing power and margin resilience than low-cost peers.
• Berkshire reduces Chevron by 35%: This is a meaningful trim of a major position. Whether driven by valuation, a portfolio rebalancing decision, or a dimmer view on energy sector returns is unclear from the filing alone.
• Li Lu of Himalaya Capital sells 71% of Bank of America: Li Lu managed money for Charlie Munger and is one of the more quietly respected value investors in the US. A 71% reduction is a substantial move, though the rationale is not publicly available.
• Mohnish Pabrai reduces offshore drilling exposure: Pabrai sold out of Valaris and cut 25% from Transocean, both offshore drilling operators. His metallurgical coal thesis remains intact.
• Bill Ackman exits Hilton after seven years: Hilton has been a core Pershing Square holding since 2018 and delivered strong returns. The exit likely reflects the position reaching or exceeding Ackman's estimate of intrinsic value rather than any negative view on the business.

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The Macro Pattern Connecting These Moves

Read across these filings collectively and a clear investment thesis emerges among the world's top money managers:

High-quality technology businesses temporarily punished by CapEx anxiety represent the best risk-adjusted opportunities available right now.

Microsoft, Amazon, and Alphabet are three of the most profitable, cash-generative, competitively entrenched businesses in modern economic history. All three experienced sharp sell-offs driven primarily by investor anxiety about elevated capital expenditure — not by any deterioration in their core businesses.

The managers buying into these dips are not momentum traders. Ackman, Klarman, and the Berkshire team are not chasing trends. They are applying the same analytical framework they have used for decades: assess business quality, estimate intrinsic value, wait for the market to offer a discount, and buy deliberately.

The secondary pattern is equally instructive: portfolio housekeeping is real and consequential. Berkshire's mass liquidation of 16 positions signals that new leadership brings new priorities. Investors who assume continuity across a manager transition may be surprised by the resulting portfolio changes.

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What Retail Investors Can Take Away From This Round of 13F Filings

13F filings carry inherent limitations. They reflect holdings as of quarter-end and are disclosed with a 45-day lag — meaning positions may have changed significantly by the time the data becomes public. They do not capture short positions, options strategies, or non-US holdings. They are a rear-view mirror, not a windshield.

With those caveats stated clearly, the filings remain one of the most accessible and analytically useful public datasets available to retail investors. Here is how to use them intelligently:

• Use filings to generate ideas, not decisions. When a manager of Klarman's calibre adds 47% to a position, that is a strong signal to begin your own research — not to mirror the trade blindly.
• Track position sizing, not just names. A new position worth 0.01% of a portfolio is noise. A position that moves into the top five holdings is a genuine conviction bet.
• Cross-reference across managers. When multiple independent, high-quality investors are adding to the same name — as happened with Amazon this quarter — the convergence is worth investigating seriously.
• Look for what is being sold as much as what is being bought. Exits often reveal as much about valuation discipline as new purchases do.
• Maintain your own watch list. The opportunity Klarman captured in Amazon's February sell-off was only available to investors who already understood the business and had a price target in mind. Preparation precedes opportunity.

The super investors are not omniscient. They make mistakes. But their process — disciplined, evidence-based, patient — is worth studying regardless of whether you ultimately follow their specific positions.

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This article is for informational purposes only and does not constitute financial advice. Always consult a qualified financial professional before making investment decisions.

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Frequently Asked Questions

What is a 13F filing and who has to file one? A 13F filing is a quarterly disclosure required by the US Securities and Exchange Commission (SEC) from any institutional investment manager with at least $100 million in assets under management. The filing must list all US equity holdings as of the last trading day of each quarter and be submitted within 45 days of quarter-end. It covers long positions in stocks, ETFs, and certain options — but does not require disclosure of short positions or non-US securities.

How reliable are 13F filings as investment signals? They are useful but imperfect. Because filings are published up to 45 days after quarter-end, the data reflects past positions rather than current ones. A manager may have bought and sold a position entirely within a single quarter without it appearing in the filing. That said, large positions held by high-conviction investors with long track records — particularly those representing 5% or more of a portfolio — tend to reflect durable theses worth investigating. Use filings as a research starting point, not a trade-copying tool.

Why did Berkshire Hathaway sell so many positions at once? Berkshire exited 16 positions in a single quarter — an unusually large cull for a portfolio known for its long holding periods. The most credible explanations are twofold. First, Greg Abel's transition into the CEO role likely prompted a portfolio review and consolidation around higher-conviction positions. Second, many of the exited names appear linked to Todd Combs, a former Berkshire portfolio manager who recently departed. His smaller, more diversified satellite positions may simply not fit Abel's more concentrated approach. No official explanation has been provided.

What is the difference between Alphabet Class A and Class C shares? Alphabet's Class A shares (ticker: GOOGL) carry one vote per share, giving holders a degree of influence over corporate governance decisions. Class C shares (ticker: GOOG) carry no voting rights but are otherwise economically equivalent — they represent the same ownership stake in the company's earnings and assets. For most retail investors, the voting distinction is irrelevant in practice, and both share classes tend to trade at very similar prices. Berkshire's decision to hold both classes suggests a straightforward capital allocation decision rather than a governance strategy.

Should retail investors copy what super investors buy in 13F filings? Directly mirroring 13F filings without independent analysis is not recommended. By the time a filing becomes public, the market may have already priced in the disclosed positions, eliminating the original entry-point advantage. More importantly, your own financial situation, risk tolerance, time horizon, and existing portfolio are different from any institutional manager's. The most productive way to use 13F data is as a curated idea-generation tool: when a manager with a strong long-term track record makes a large, concentrated new bet, that is a signal to start your own research — not to place an immediate order.