Route One Investment Company, L.P. In its 13F for Q4 2025 (holdings as of December 31, 2025, filed February 17, 2026), Route One Investment Company, L.P. reported 15 stock positions worth $2.4 billion . Its top holding was Guidewire Software (GWRE) at 14.0% of the portfolio, followed by Post (POST, 13.0% ) and Amazon.com (AMZN, 11.0% ). Compared with Q3 2025, it opened 2 new positions, sold out of 3, added to 3 and reduced 7. The biggest buy was a new position in Essex Property Trust (ESS) and the biggest sale an exit from Bellring Brands (BRBR).
Location San Francisco, CA
CIK 0001512171
Portfolio Value $2.4B (Q4 2025) Holdings 15 stocks · $2.4B Holdings quarter Q2 2026 Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024 Q2 2024 Q1 2024
Stock % Of Portfolio ▼ Shares Held Total Value Change vs Q3 2025 GWRE Guidewire Software Inc. 1,670,414 $335.8M Reduce -8.1% POST Post Holdings Inc. filed as POST HLDGS INC 3,136,468 $310.7M Reduce -8.6% AMZN Amazon.com Inc. 1,138,000 $262.7M Reduce -10.8% GOOG Alphabet Inc. Class C 689,080 $216.2M Reduce -7.5% NYT New York Times Co. Class A 3,105,309 $215.6M Reduce -16.1% SCHW Schwab (charles) Corp. 1,838,343 $183.7M Reduce -18.1% UNH Unitedhealth Group Inc. 507,300 $167.5M No change TMO Thermo Fisher Scientific Inc. 263,600 $152.7M Reduce -10.2% ESS Essex Property Trust Inc. 532,977 $139.5M New KRC Kilroy Realty Corp. 2,935,372 $109.7M Add +12.1% HLF Herbalife Ltd. 8,162,123 $105.2M Add +8.4% PCOR Procore Technologies Inc. 918,205 $66.8M No change VIST Vista Energy Sab DE CV 1,024,200 $49.8M New TBBB BBB Foods Inc. Class A 1,385,196 $46.3M Add +1673.2% VEEV Veeva Systems Inc. Class A 155,100 $34.6M No change
Options reported separately and not counted above: IWM puts ($295.4M).
Portfolio Sells Q3 2025 → Q4 2025 Portfolio Sells quarter Q2 2026 Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024 Q2 2024 Q1 2024
Stock Change vs Q3 2025 % Of Portfolio Change To Portfolio ▲ BRBR Bellring Brands Inc. Sold out 0.00% −3.42 CRM Salesforce Inc. Sold out 0.00% −3.27 GWRE Guidewire Software Inc. Reduce -8.1% 14.01% −3.04 POST Post Holdings Inc. Reduce -8.6% 12.96% −2.09 SCHW Schwab (charles) Corp. Reduce -18.1% 7.66% −1.08 AMZN Amazon.com Inc. Reduce -10.8% 10.96% −0.48 GOOGL Alphabet Inc. Class A Sold out 0.00% −0.20 NYT New York Times Co. Class A Reduce -16.1% 8.99% +0.33 TMO Thermo Fisher Scientific Inc. Reduce -10.2% 6.37% +0.57 GOOG Alphabet Inc. Class C Reduce -7.5% 9.02% +1.62
Portfolio Buys Q3 2025 → Q4 2025 Portfolio Buys quarter Q2 2026 Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024 Q2 2024 Q1 2024
Stock Change vs Q3 2025 % Of Portfolio Change To Portfolio ▼ ESS Essex Property Trust Inc. New 5.82% +5.82 VIST Vista Energy Sab DE CV New 2.08% +2.08 TBBB BBB Foods Inc. Class A Add +1673.2% 1.93% +1.84 HLF Herbalife Ltd. Add +8.4% 4.39% +1.80 KRC Kilroy Realty Corp. Add +12.1% 4.58% +0.06
Options Activity Q3 2025 → Q4 2025 Security Type Change vs Q3 2025 Underlying Shares Value ▼ IWM iShares Russell 2000 ETF put New 1,200,000 $295.4M GOOGL Alphabet Inc. Class A put Sold out 800,000 $194.5Mbefore exit
Calls and puts are listed by the shares they cover; their value is not part of the stock holdings above.
Notes & Other Activity Q3 2025 → Q4 2025 Bonds, preferreds, convertibles and warrants; not part of the stock holdings or percentages above.
All Filings Quarter Positions 13F Reported Value Top Holdings Q2 2026 19 $2.4B POST, AMZN, GWRE, GOOG, UNH Q1 2026 18 $2.3B POST, GWRE, AMZN, NYT, GOOG Q4 2025 15 $2.4B GWRE, POST, AMZN, GOOG, NYT Q3 2025 16 $2.5B GWRE, POST, AMZN, SCHW, NYT Q2 2025 14 $2.2B GWRE, POST, AMZN, SCHW, NYT Q1 2025 13 $2.3B POST, GWRE, SCHW, AMZN, UNH Q4 2024 13 $2.5B POST, GWRE, AMZN, SCHW, UNH Q3 2024 15 $2.8B GWRE, POST, AMZN, UNH, SCHW Q2 2024 15 $2.6B POST, GWRE, AMZN, UNH, GOOG Q1 2024 16 $2.5B POST, GWRE, AMZN, UNH, CRM