Understanding Financial Security Identifiers

Quick Comparison Table

Ticker Symbols

What Are Ticker Symbols?

Ticker symbols are short alphabetic codes (1-5 letters) that identify publicly traded companies on a specific exchange.

Examples

• AAPL - Apple Inc. (NASDAQ)
• MSFT - Microsoft Corp (NASDAQ)
• BRK-A - Berkshire Hathaway Class A (NYSE)
• GOOGL - Alphabet Inc. Class A (NASDAQ)

Ticker Symbol Conventions

Exchange-Specific Suffixes

Different platforms add exchange identifiers:

• Bloomberg: AAPL US Equity
• Reuters: AAPL.O (O = NASDAQ)
• Yahoo: AAPL (US), VOD.L (London)
• Google: NASDAQ:AAPL

When to Use Tickers

• Trading platforms and displays
• News and financial websites
• Portfolio tracking apps
• Market data feeds

Ticker Limitations

• Not globally unique (different exchanges may reuse)
• Can change over time (mergers, rebranding)
• Don't identify specific share classes without suffix
• Exchange-dependent

ISIN (International Securities Identification Number)

Structure

12 alphanumeric characters:

• Positions 1-2: Country code (ISO 3166-1)
• Positions 3-11: National security identifier (9 characters)
• Position 12: Check digit (Luhn algorithm)

Examples

• US0378331005 - Apple Inc. (US)
• GB0002374006 - Diageo PLC (UK)
• DE0005140008 - Deutsche Bank (Germany)

ISIN Country Codes

When to Use ISINs

• Cross-border trading
• Regulatory reporting (MiFID II, EMIR)
• Global custody and settlement
• International portfolio management

CUSIP (Committee on Uniform Securities Identification Procedures)

Structure

9 alphanumeric characters used in US and Canada:

• Positions 1-6: Issuer identifier
• Positions 7-8: Issue identifier
• Position 9: Check digit

Examples

• 037833100 - Apple Inc. common stock
• 459200101 - IBM common stock
• 594918104 - Microsoft common stock

CUSIP Relationship to ISIN

US ISINs incorporate the CUSIP:

CUSIP:  037833100
ISIN:   US0378331005
        ↑↑ ↑↑↑↑↑↑↑↑↑ ↑
        CC  CUSIP    Check

When to Use CUSIPs

• US/Canada securities trading
• SEC Form 13F filings
• Municipal bonds
• US government securities

SEDOL (Stock Exchange Daily Official List)

Structure

7 alphanumeric characters used primarily for UK and Irish securities:

• Positions 1-6: Unique identifier
• Position 7: Check digit

Examples

• 2046251 - Vodafone Group
• 0263494 - BP PLC
• B10RZP7 - Barclays PLC

SEDOL in ISINs

UK ISINs incorporate the SEDOL:

SEDOL:  2046251
ISIN:   GB0002046251
        ↑↑ 000↑↑↑↑↑↑↑ ↑
        CC Pad SEDOL Check

When to Use SEDOLs

• London Stock Exchange trading
• UK/Irish securities
• European fund administration

Other Identifier Systems

FIGI (Financial Instrument Global Identifier)

Bloomberg's open standard:

• 12 characters (alphanumeric)
• Free to use via OpenFIGI API
• Example: BBG000B9XRY4 (Apple)
• Maps to ISINs and other identifiers

RIC (Reuters Instrument Code)

Reuters/Refinitiv system:

• Variable length
• Format: TICKER.EXCHANGE
• Example: AAPL.O (Apple on NASDAQ)
• Used in Reuters terminals

LEI (Legal Entity Identifier)

Identifies legal entities (companies):

• 20 characters
• Example: 549300K6KWD1H0P6FU89
• Used for regulatory reporting
• Entity-level, not security-level

Choosing the Right Identifier

Decision Matrix

Multi-Identifier Strategy

Best practice: Store multiple identifiers

CREATE TABLE securities (
    isin CHAR(12) PRIMARY KEY,
    cusip CHAR(9),
    sedol CHAR(7),
    ticker VARCHAR(10),
    figi CHAR(12),
    name VARCHAR(255),
    exchange VARCHAR(50)
);

Common Issues and Solutions

Issue #1: Identifier Mismatches

Problem: Same security, different identifiers across systems

Solution: Use reference data providers (Bloomberg, Refinitiv) or OpenFIGI API to map between identifiers

Issue #2: Ticker Changes

Problem: Company renames, ticker changes

Solution: Use ISIN as permanent identifier, ticker as display only

Issue #3: Multiple Share Classes

Problem: GOOGL vs GOOG (Alphabet A vs C shares)

Solution: Always use full identifier (ISIN/CUSIP) for precision