Optimized Portfolio as Listed Securities (OPALS)
A portfolio of securities used to closely track an index without the exposure of purchasing all securities within that index.

Investopedia Says:
OPALS are similar to ETFs and are generally used by large institutional investors because there are usually minimum requirements associated with them.

Related Terms:
ETF
Institutional Investor

• Statement of Additional Information (SAI)
• Statement of Financial Accounting Concepts (SFAC)
• Statement of Financial Accounting Concepts (SFAC)
• Statement of Financial Accounting Standards (SFAS)
• Statement of Financial Accounting Standards (SFAS)
• Static Budget
• Static Spread
• Statistical Arbitrage
• Statistically Significant
• Statistics
• Statutory Accounting Principles (SAP)
• Statutory Accounting Principles (SAP)
• Statutory Voting
• STD
• Stem The Tide
• Step-out Trading
• Step-Up Bond
• Step-Up In Basis
• Sterile Investment
• Sterilization
• Sterilized Intervention
• Sterling Overnight Interbank Average Rate (SONIA)
• Sterling Ratio
• Stewardship Grade
• Sticky Deal