Alex Rivera
Breaking News Editor
Breaking News Editor at 13F Insight. First to report on major SEC filings, institutional moves, and regulatory developments.
A note from Alex
Hey, I'm Alex. I spent three and a half years at Bloomberg writing breaking-news pieces about the kind of trades that move tickers in after-hours, and what I learned is that the news cycle moves a lot faster than the explanations do.
That's the gap I'm here to close. When a major insider files a Form 4 at 4:31pm, you should know about it by 5:00 — not in tomorrow's morning newsletter. And you should know what's actually new about it, not just that it happened.
I'll keep my pieces short, my numbers exact, and my opinions out of the lede. If something I wrote ages badly, I'll say so on the record.
Articles by Alex Rivera (691)
- Research
Harnisch Put 91% of Peconic’s $4.2B Into Three Infrastructure Stocks After Returning 79% in 2025: The Power Grid Play That Crushed the S&P 500
Bill Harnisch’s Peconic Partners exploded from $140M to $4.2B in Q4 2025 by going all-in on Quanta Services, Dycom, and MasTec — the companies building the power lines and fiber networks behind AI, broadband, and clean energy.
- Research
Abrams Capital Put 38% of a $5.7B Portfolio Into One Aerospace Stock While Building a $1.3B Auto Dealership Empire: Inside the Klarman Protégé's Q4 2025 Conviction Bet
David Abrams — Seth Klarman's former protégé — held 32 million LOAR shares worth $2.2B at 38.4% of portfolio in Q4 2025 while deploying $1.33B into Lithia Motors and Asbury Automotive, the two largest US auto dealership chains. 12 holdings, 3 stocks = 62% of the portfolio.
- Research
Akre Deployed $2.65B Into 8 New Positions After Pruning to Just 11 Holdings: Inside the Compounding Machine Reload of Q4 2025
Akre Capital rebuilt its portfolio from 11 to 18 holdings in Q4 2025, deploying $2.65B into Moody’s, Airbnb, FICO, and Roper Technologies while increasing Brookfield by 40% — the most aggressive single-quarter expansion in the fund’s recent history.
- Research
Gates Sold $1.9B of Berkshire and Microsoft in Q4 as the Foundation's 20-Year Self-Destruct Accelerates: Inside the $35.4B Blue-Chip Portfolio
The Gates Foundation Trust sold 2.36M Berkshire and 1.5M Microsoft shares in Q4 2025 — its only two trades — as Bill Gates's 20-year sunsetting plan systematically unwinds a $35.4B blue-chip portfolio.
- Research
Soros Bought $578M in Energy Puts While Einhorn Loaded Gold Bars: Inside the Great Commodity Divergence of Q4 2025
Gold surged 60% in 2025 while oil crashed 15%. Seven whale funds split into three camps: gold bulls (Einhorn, Bridgewater), energy concentrated (Icahn at 76%, Berkshire at $31B), and the macro hedge (Soros shorting energy with $578M in puts while buying gold miners). The data reveals the widest commodity positioning gap since 2020.
- Research
Third Point Cut 15.8M PG&E Shares and Doubled Union Pacific to $419M: Inside Loeb's Q4 2025 Railroad Pivot
Dan Loeb's Third Point sold 15.8 million PG&E shares (-32%) — unwinding the decade's most famous utility activist bet — and simultaneously doubled Union Pacific to $419M (+107%). With $719M across three railroads and 14 new positions including Chipotle and Alibaba, the $7.3B Q4 2025 filing reveals an activist fund pivoting from utilities to transport infrastructure.
- Research
Elliott Nearly Doubled to $22.6B in One Quarter: The Activist Playbook Behind $6.9B in New Campaign Positions
Elliott nearly doubled its 13F from $11.7B to $22.6B in Q4 2025, deploying $6.9B across activist targets Phillips 66, Suncor, and Southwest Airlines. Gold hedge held firm at $5.8B as the world's most active activist reloaded for parallel campaigns.
- Research
Insiders Put $12 Billion of Their Own Money In During Q4 2025: The 10 Companies Executives Bought Most Aggressively
Nearly 1,700 corporate insiders collectively spent $12 billion buying their own companies' stock in Q4 2025. From a $7.6 billion biotech mega-deal to a DoorDash board member's $100 million conviction bet, here's where executives put their money where their mouth is.
- Research
Tiger Global +42.47% but 13-Point De-Crowding: The Q4 2025 Mega-Cap Rebalance
Tiger Global's Q4 2025 13F rose 42.47% in value while top-10 concentration dropped 13.06 points, led by large new stakes in MSFT, AMZN, TTWO, and TSM.
- Research
Lone Pine's $5.3B Quarter: Portfolio Jumped 64% While Holdings Doubled from 15 to 32
Lone Pine Capital's Q4 2025 13F shows a dramatic scale-up with breadth expansion, a full META exit, and a new CVNA position entering the top three.
- Research
Appaloosa Cut Alibaba Weight by 21.2 Points While Doubling 13F Size and More Than Doubling Holdings Breadth
Appaloosa's Q4 2025 13F shows a dramatic concentration reset: Alibaba weight fell from 32.07% to 10.88% as portfolio value rose 92.67% and holdings breadth more than doubled.