OSTGX — Osterweis Opportunity Fund
Data updated: 2026-08-21
OSTGX — Osterweis Opportunity Fund. United States Small Cap Growth Equity · $382.66M AUM · 1.12% expense ratio. Holdings, fees, performance and SEC filings.
OSTGX Fund Overview
OSTGX — Osterweis Opportunity Fund is a US mutual fund managed by Professionally Managed Portfolios, categorised as United States Small Cap Growth Equity. ABC INVEST provides holdings, performance, costs, cashflows, risk data, prospectus documents and SEC filings, sourced from SEC filings.
- Type: US mutual fund
- Manager: Professionally Managed Portfolios
- Category: United States Small Cap Growth Equity
- Assets under management: $382.66M
- 1-year return: 41.4%
- Ticker: OSTGX
- SEC CIK: 0000811030
- SEC series ID: S000055531
- Share class ID: C000174818
OSTGX Holdings
Top 10 holdings of Osterweis Opportunity Fund by percentage of net assets, from the fund's latest SEC N-PORT filing.
| Holding | % of net assets |
|---|---|
| Federated Hermes US Treasury C | 9.01% |
| Vericel Corp | 3.54% |
| Life Time Group Holdings Inc | 3.49% |
| SPX Technologies Inc | 3.47% |
| Novanta Inc | 3.40% |
| Cardinal Infrastructure Group | 3.37% |
| VSE Corp | 3.27% |
| Twilio Inc | 3.11% |
| Loar Holdings Inc | 3.04% |
| Repligen Corp | 3.02% |
OSTGX Portfolio Allocation
Asset-class allocation of Osterweis Opportunity Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Asset class | Allocation |
|---|---|
| Equity | 91.1% |
| Cash & Equivalents | 9.0% |
OSTGX Performance
Total returns for OSTGX (as of 2026-09-01), from SEC filings.
| Period | Total return |
|---|---|
| YTD | 30.2% |
| 1 year | 41.4% |
| 3 years (annualised) | 18.2% |
| 5 years (annualised) | 5.1% |
OSTGX Risk Information
Risk metrics for OSTGX, derived from monthly returns in SEC filings.
- 1-year volatility (annualised): 18.7%
OSTGX Costs and Fees
OSTGX costs about $112 per $10,000 invested per year in fund expenses.
- Net expense ratio: 1.12%
- Gross expense ratio: 1.22%
- Portfolio turnover: 178%
- Brokerage commissions: 26.15 bps of average net assets (SEC N-CEN)
OSTGX Cashflows
Over the 12 months to 2026-06, Osterweis Opportunity Fund had net outflows of $42.63M, from monthly SEC N-PORT filings.
| Month | Net flow |
|---|---|
| 2026-06 | −$1.53M |
| 2026-05 | −$1.26M |
| 2026-04 | −$2.46M |
| 2026-03 | −$834.88K |
| 2026-02 | −$3.66M |
| 2026-01 | −$4.09M |
OSTGX Debt Constituents
No individual debt constituents are reported in Osterweis Opportunity Fund's latest SEC N-PORT filing.
OSTGX Prospectus and SEC Filings
Official Osterweis Opportunity Fund filings on SEC EDGAR — prospectus, portfolio holdings and annual reports.
- Prospectus (485BPOS) — filed 2026-06-30
- Prospectus (485BPOS) — filed 2025-06-27
- Prospectus (485BPOS) — filed 2024-06-28
- Portfolio holdings (N-PORT) — filed 2026-08-21
- Portfolio holdings (N-PORT) — filed 2026-05-28
- Portfolio holdings (N-PORT) — filed 2026-02-18
- Annual census (N-CEN) — filed 2026-06-11
- Annual census (N-CEN) — filed 2025-06-10
Related Funds
Other United States Small Cap Growth Equity funds tracked on ABC INVEST:
Data Sources
ABC INVEST compiles this page from public filings made to the U.S. Securities and Exchange Commission (SEC) through EDGAR: portfolio holdings and monthly cashflows from Form N-PORT, expenses and returns from fund prospectuses (Form 485BPOS) and the SEC DERA Risk/Return Summary data sets, annual data from Form N-CEN, and shareholder reports from Form N-CSR.