Skip to content

Matching Behavior

This page describes what happens to a license string before and during lookup.

Quote Normalization

Before lookup, LicenseLynx normalizes recognized Unicode quote characters to the ASCII single quote '.

This helps when license strings are copied from PDFs, websites, office documents, or other sources that use typographic quotes.

Examples:

  • BSD ‚Zero‛ Clause becomes BSD 'Zero' Clause
  • Licensed under the “MIT” license becomes Licensed under the 'MIT' license

Lookup Order

Lookup happens in this order:

  1. Normalize quote characters.
  2. Search the stable map.
  3. If risky is enabled, search the risky map.
  4. If org is provided, search the organization-specific map.

See Risky Mappings for the meaning of the risky map.

Recognized Quote Characters

All three libraries normalize the same set of characters:

quote_characters = [
    # Single quotes
    "\u2018",  # LEFT SINGLE QUOTATION MARK '
    "\u2019",  # RIGHT SINGLE QUOTATION MARK '
    "\u201A",  # SINGLE LOW-9 QUOTATION MARK ‚
    "\u201B",  # SINGLE HIGH-REVERSED-9 QUOTATION MARK ‛
    "\u2032",  # PRIME (often used as an apostrophe) ′
    "\uFF07",  # FULLWIDTH APOSTROPHE ＇
    # Double quotes
    "\u201C",  # LEFT DOUBLE QUOTATION MARK "
    "\u201D",  # RIGHT DOUBLE QUOTATION MARK "
    "\u201E",  # DOUBLE LOW-9 QUOTATION MARK „
    "\u201F",  # DOUBLE HIGH-REVERSED-9 QUOTATION MARK ‟
    "\u2033",  # DOUBLE PRIME ″
    "\u00AB",  # LEFT-POINTING DOUBLE ANGLE QUOTATION MARK «
    "\u00BB",  # RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK »
    "\uFF02",  # FULLWIDTH QUOTATION MARK ＂
]