Osterweis Capital Management Inc holds a diversified book of 229 stocks worth $1.9B as of Q1 2026 (disclosed May 15, 2026, a ~45-day 13F lag). This quarter they opened Affirm Holdings Inc and trimmed Alphabet Inc-CL C. Their largest long position is Alphabet Inc-CL C at 5% of the equity book.
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curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/funds/1007524/holdings"
Use Arkolith to show OSTERWEIS CAPITAL MANAGEMENT INC's latest holdings, largest changes, and filing provenance.
Top-heavy: diversified book
Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.
84% mapped to company sectors
Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.
Estimated $ traded · quarter-end prices, no cost basis
Bars show each stock's share of the portfolio. Click a row for its position history.
| # | Security | Value | Shares | % Port | Last move | History |
|---|---|---|---|---|---|---|
| 1 | Alphabet Inc CAP STK CL C | $93.8M | 327.2K | 4.8% | ▼−8.9% Reduced · −32K sh | |
| 2 | Affirm Hldgs Inc NOTE 11/1 | $55.8M | 57.50M | 2.9% | ▲New New position | |
| 3 | Amazon Com Inc COM | $54.0M | 259.1K | 2.8% | ▼−23% Reduced · −77K sh | |
| 4 | Microsoft Corp COM | $53.6M | 144.7K | 2.8% | ▼−18% Reduced · −32K sh | |
| 5 | Applied Matls Inc COM | $48.6M | 142.1K | 2.5% | ▼−7.0% Reduced · −11K sh | |
| 6 | Marriott Vacations Worldwide NOTE 3.250%12/1 | $48.1M | 50.00M | 2.5% | ▲New New position | |
| 7 | Broadcom Inc COM | $48.0M | 155.1K | 2.5% | ▼−15% Reduced · −27K sh | |
| 8 | Analog Devices Inc COM | $47.8M | 150.3K | 2.5% | ▼−1.1% Reduced · −2K sh | |
| 9 | Visa Inc COM CL A | $43.5M | 143.9K | 2.2% | ▲+1.9% Added · +3K sh | |
| 10 | Autozone Inc COM | $42.6M | 12.6K | 2.2% | ▲+11% Added · +1K sh | |
| 11 | JPMorgan Chase & Co COM | $41.6M | 141.5K | 2.1% | ▲+1.8% Added · +2K sh | |
| 12 | JBT Marel Corporation NOTE 0.250% 5/1 | $41.2M | 41.28M | 2.1% | ▲10× Added · +37.2M sh | |
| 13 | Eli Lilly & Co COM | $41.2M | 44.8K | 2.1% | ▲~0% Added · +10 sh | |
| 14 | Nvidia Corporation COM | $39.9M | 228.7K | 2.1% | ▲+73% Added · +96K sh | |
| 15 | Waste Connections Inc COM | $39.1M | 240.8K | 2.0% | ▲+1.3% Added · +3K sh | |
| 16 | Danaher Corp Del COM | $36.2M | 191.0K | 1.9% | ▲+1.5% Added · +3K sh | |
| 17 | Penn Entertainment Inc NOTE 2.750% 5/1 | $35.5M | 35.45M | 1.8% | ▲New New position | |
| 18 | Q2 Hldgs Inc NOTE 0.750% 6/0 | $35.3M | 35.43M | 1.8% | ▲New New position | |
| 19 | American WTR WKS Co Inc New COM | $34.9M | 256.4K | 1.8% | ▼−15% Reduced · −47K sh | |
| 20 | Terreno Rlty Corp COM | $34.1M | 555.7K | 1.8% | ▼−3.4% Reduced · −20K sh | |
| 21 | Air Products And Chemicals I COM | $33.2M | 114.4K | 1.7% | ▼−20% Reduced · −29K sh | |
| 22 | Pebblebrook Hotel TR NOTE 1.750%12/1 | $33.1M | 33.87M | 1.7% | ▲+282% Added · +25.0M sh | |
| 23 | US Foods Hldg Corp COM | $32.6M | 354.1K | 1.7% | ▼−9.6% Reduced · −37K sh | |
| 24 | Keysight Technologies Inc COM | $32.6M | 115.4K | 1.7% | ▼−23% Reduced · −35K sh | |
| 25 | L3harris Technologies Inc COM | $31.0M | 89.9K | 1.6% | ▼−18% Reduced · −19K sh | |
| 26 | Ziff Davis Inc NOTE 1.750%11/0 | $30.1M | 30.59M | 1.6% | ▲+189% Added · +20.0M sh | |
| 27 | Progressive Corp COM | $28.7M | 144.8K | 1.5% | ▼−4.3% Reduced · −7K sh | |
| 28 | Intercontinental Exchange In COM | $27.8M | 176.9K | 1.4% | ▲+1.3% Added · +2K sh | |
| 29 | Boston Scientific Corp COM | $27.7M | 442.2K | 1.4% | ▲+64% Added · +173K sh | |
| 30 | Ferguson Enterprises Inc COMMON STOCK NEW | $27.5M | 117.7K | 1.4% | ▼−1.3% Reduced · −2K sh | |
| 31 | Brown & Brown Inc COM | $25.9M | 397.3K | 1.3% | ▼−6.7% Reduced · −28K sh | |
| 32 | Lamar Advertising Co CL A | $25.5M | 201.2K | 1.3% | ▼−21% Reduced · −55K sh | |
| 33 | Canadian Pacific Kansas City COM | $25.3M | 322.2K | 1.3% | ▼−0.4% Reduced · −1K sh | |
| 34 | Ametek Inc COM | $25.1M | 116.9K | 1.3% | ▼−18% Reduced · −26K sh | |
| 35 | Deere & Co COM | $24.5M | 43.5K | 1.3% | ▼−0.1% Reduced · −43 sh | |
| 36 | Abbvie Inc COM | $23.4M | 107.5K | 1.2% | ▲29× Added · +104K sh | |
| 37 | Boeing Co COM | $21.7M | 109.1K | 1.1% | ▲+0.4% Added · +405 sh | |
| 38 | Public Storage Oper Co COM | $21.3M | 78.8K | 1.1% | ▲New New position | |
| 39 | Labcorp Holdings Inc COM SHS | $20.5M | 77.0K | 1.1% | ▲+1.2% Added · +920 sh | |
| 40 | SLB Limited COM STK | $19.2M | 373.3K | 1.0% | ▲New New position | |
| 41 | NVR Inc COM | $18.0M | 2.7K | 0.9% | ▲+3.8% Added · +100 sh | |
| 42 | Synopsys Inc COM | $17.5M | 44.0K | 0.9% | ▲+1.8% Added · +783 sh | |
| 43 | Upwork Inc NOTE 0.250% 8/1 | $14.4M | 14.68M | 0.7% | ▲New New position | |
| 44 | Meta Platforms Inc CL A | $14.3M | 25.1K | 0.7% | ▼−0.8% Reduced · −195 sh | |
| 45 | Life Time Group Holdings Inc COMMON STOCK | $14.0M | 519.6K | 0.7% | ▲+7.6% Added · +37K sh | |
| 46 | Axos Financial Inc COM | $13.9M | 163.7K | 0.7% | ▲+15% Added · +21K sh | |
| 47 | Guardant Health Inc COM | $13.8M | 148.9K | 0.7% | ▲+9.6% Added · +13K sh | |
| 48 | Ceco Environmental Corp COM | $13.5M | 226.6K | 0.7% | ▲+1.3% Added · +3K sh | |
| 49 | Vse Corp COM | $13.4M | 72.6K | 0.7% | ▲+50% Added · +24K sh | |
| 50 | Vericel Corp COM | $12.9M | 401.0K | 0.7% | ▲+24% Added · +78K sh |
As-of date vs the date the SEC received each filing
| Quarter | As of | Filed | Positions | Value | Form |
|---|---|---|---|---|---|
| Q1 2026 | Mar 31, 2026 | May 15, 2026 | 277 | $1.9B | 13F-HR |
| Q4 2025 | Dec 31, 2025 | Feb 17, 2026 | 331 | $2.4B | 13F-HR |
| Q3 2025 | Sep 30, 2025 | Nov 14, 2025 | 320 | $2.2B | 13F-HR |
| Q2 2025 | Jun 30, 2025 | Aug 14, 2025 | 327 | $2.1B | 13F-HR |
| Q1 2025 | Mar 31, 2025 | Jun 5, 2025 | 383 | $2.0B | 13F-HR/A |
| Q4 2024 | Dec 31, 2024 | Jun 5, 2025 | 246 | $2.1B | 13F-HR/A |
| Q3 2024 | Sep 30, 2024 | Nov 14, 2024 | 240 | $2.0B | 13F-HR |
| Q2 2024 | Jun 30, 2024 | Aug 14, 2024 | 243 | $1.9B | 13F-HR |
| Q1 2024 | Mar 31, 2024 | May 15, 2024 | 236 | $1.7B | 13F-HR |
| Q4 2023 | Dec 31, 2023 | Feb 14, 2024 | 244 | $1.6B | 13F-HR |
| Q3 2023 | Sep 30, 2023 | Nov 14, 2023 | 251 | $1.4B | 13F-HR |
| Q2 2023 | Jun 30, 2023 | Aug 14, 2023 | 256 | $1.5B | 13F-HR |
| Q1 2023 | Mar 31, 2023 | May 15, 2023 | 259 | $1.5B | 13F-HR |
| Q4 2022 | Dec 31, 2022 | Feb 14, 2023 | 284 | $1.4B | 13F-HR |
| Q3 2022 | Sep 30, 2022 | Nov 14, 2022 | 285 | $1.3B | 13F-HR |
| Q2 2022 | Jun 30, 2022 | Aug 15, 2022 | 181 | $1.3B | 13F-HR |
| Q1 2022 | Mar 31, 2022 | May 16, 2022 | 194 | $1.8B | 13F-HR |
| Q4 2021 | Dec 31, 2021 | Feb 14, 2022 | 197 | $2.0B | 13F-HR |
| Q3 2021 | Sep 30, 2021 | Nov 15, 2021 | 196 | $1.8B | 13F-HR |
| Q2 2021 | Jun 30, 2021 | Aug 16, 2021 | 194 | $1.9B | 13F-HR |
| Q1 2021 | Mar 31, 2021 | May 14, 2021 | 185 | $1.8B | 13F-HR |
| Q4 2020 | Dec 31, 2020 | Feb 12, 2021 | 175 | $1.7B | 13F-HR |
Holdings from SEC EDGAR 13F-HR filings, updated quarterly ~45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. Price-derived performance is withheld until the price-source policy and freshness gate are green.