Naming Conventions

IDs follow consistent patterns based on the hierarchy:

Complete Hierarchy

Category → Subcategory → Series → Event + Product → Instrument

Example:

SPR → SOCCER → MLS → mls-atl-clt-2026-03-22 + ATC → atc-mls-atl-clt-2026-03-22-draw

Event ID Format

Events are identified by series, descriptors, and date/time:

{series}-{descriptors}-{date/time}

Sports:

nfl-ne-den-2026-01-25
mls-atl-clt-2026-03-22

Politics:

uspres-2028-11-05
ussen-2026-11-03

Crypto:

btc-hit-2026-12-31
eth-hit-2027-06-30

Culture:

oscars-2027-03-28
grammys-2027-02-14

Instrument ID Format

Instruments combine product, event, and outcome:

{product_code}-{event_id}-{strike/outcome}

Examples:

aec-nfl-ne-den-2026-01-25 - Moneyline (no additional outcome)
atc-mls-atl-clt-2026-03-22-draw - 3-way outcome: draw
atc-mls-atl-clt-2026-03-22-atl - 3-way outcome: Atlanta wins
asc-nfl-hou-mia-2025-12-16-pos-4pt5 - Spread: 4.5 points
tsc-nfl-ne-den-2026-01-25-47-5 - Total: 47.5 points

Participant ID Format

{series}-{abbreviation}

Examples:

nfl-ne (New England)
nfl-den (Denver)
nba-bos (Boston Celtics)
usp-harris (Kamala Harris)

Participant abbreviations are standardized across all instruments in a series to enable consistent querying and position tracking.

Participant Lookup API

Participant abbreviations and display names can be looked up via the public teams endpoint:

GET https://gateway.polymarket.us/v1/sports/teams?limit=500&filters.league={series}

Example: Fetch all MLS teams:

GET https://gateway.polymarket.us/v1/sports/teams?limit=500&filters.league=mls

Response:

{
  "teams": [
    {
      "id": "2263",
      "name": "Chicago Fire FC",
      "abbreviation": "chi",
      "league": "mls",
      "displayAbbreviation": "CHI",
      "alias": "The Fire",
      "logo": "https://polymarket-upload.s3.us-east-2.amazonaws.com/us-logos/MLS/Team%3DChicago+Fire+FC.png",
      "colorPrimary": "#5FC1EA",
      "record": "0-0-0",
      "providerIds": [
        {"provider": "PROVIDER_SPORTRADAR", "providerId": "sr:competitor:2505"},
        {"provider": "PROVIDER_SPORTSDATAIO", "providerId": "694"}
      ]
    }
  ]
}

Mapping to instrument metadata:

Teams endpoint	Instrument metadata	Example
`abbreviation`	`long_participant_id` / `short_participant_id` (as `{league}-{abbreviation}`)	`chi` → `mls-chi`
`name`	`long_participant_name` / `short_participant_name`	`Chicago Fire FC`
`league`	`event_series`	`mls`
`providerIds[SPORTSDATAIO]`	`event_external_id_sportsdataio`	`694`
`providerIds[SPORTRADAR]`	`event_external_id_sportradar`	`sr:competitor:2505`

The endpoint also provides display data not present in instrument metadata: logo, colorPrimary, alias, displayAbbreviation, and record.

Uniqueness Rules

Each level of the hierarchy has specific uniqueness scoping:

Level	Uniqueness Scope	Example
Category	Globally unique	SPR, POL, CRY
Subcategory	Unique within Category	SOCCER within SPR, COIN within CRY
Series	Unique within Subcategory	MLS within SOCCER, BTC within COIN
Event	Unique within Series (globally unique with series prefix)	`mls-atl-clt-2026-03-22`
Product	Globally unique by Code	ATC, AEC, ASC
Instrument	Globally unique	`atc-mls-atl-clt-2026-03-22-draw`

Key Points:

Events belong to exactly one Series
Products are independent and can be applied to events across any Series
Instruments are globally unique combinations of Product + Event + Outcome

Multi-Product Events

A single event can have multiple products applied to it, each creating its own set of instruments. This allows traders to speculate on the same event in different ways. Hierarchy:

SPR → FOOTBALL → NFL → nfl-ne-den-2026-01-25

Event: nfl-ne-den-2026-01-25 (New England vs Denver on Jan 25, 2026) Products Applied:

AEC (Athletic Event Contract) - Single Binary
- Instrument: aec-nfl-ne-den-2026-01-25
- Question: “Will New England win?”
- Outcome: moneyline, strike: 0.0
ASC (Athletic Spread Contract) - Group Directional
- Instrument: asc-nfl-ne-den-2026-01-25-pos-3pt5
- Question: “Will New England win by more than 3.5 points?”
- Outcome: spread, strike: 3.5
TSC (Total Score Contract) - Group Directional
- Instrument: tsc-nfl-ne-den-2026-01-25-47-5
- Question: “Will total points be over 47.5?”
- Outcome: total, strike: 47.5

All three instruments reference the same event_id but have different product codes, outcome_type, and outcome_strike values.

Soccer Example with 3-Way Markets

Hierarchy:

SPR → SOCCER → MLS → mls-atl-clt-2026-03-22

Event: mls-atl-clt-2026-03-22 (Atlanta United vs Charlotte FC) Products Applied:

ATC (Athletic Tie Contract) - Group Exclusive (3-way)
- atc-mls-atl-clt-2026-03-22-atl (Atlanta wins)
- atc-mls-atl-clt-2026-03-22-draw (Draw)
- atc-mls-atl-clt-2026-03-22-clt (Charlotte wins)
AEC (Athletic Event Contract) - Single Binary
- aec-mls-atl-clt-2026-03-22 (Will Atlanta win?)
TSC (Total Score Contract) - Group Directional
- tsc-mls-atl-clt-2026-03-22-2-5 (Over 2.5 goals)
- tsc-mls-atl-clt-2026-03-22-3-5 (Over 3.5 goals)

The same event supports both 3-way markets (ATC) and binary markets (AEC), plus totals (TSC).

Complete Metadata Reference

All metadata fields available on instruments:

Field	Level	Required	Type	Example	Description
`cftc_instrument_id`	Instrument	Yes	String	`"aec-nfl-ne-den-2026-01-25"`	CFTC registered instrument ID
`clearing_sym`	Instrument	Yes	String	`"AEC-NFL"`	Clearing symbol prefix
`event_category`	Category	Yes	String	`"SPR"`	Category code (SPR, POL, CRY, etc.)
`event_series`	Series	Yes	String	`"nfl"`	Series code within category
`instrument_product`	Product	Yes	String	`"aec"`	Product type code
`instrument_product_series`	Product	Yes	String	`"aec-nfl"`	Combined product and series
`product_id`	Product	Yes	String	`"aec-nfl-ne-den-2026-01-25"`	Product identifier
`event_id`	Event	Yes	String	`"nfl-ne-den-2026-01-25"`	Unique event identifier
`event_start_time`	Event	Yes	Timestamp	`"2026-01-25 20:00:00+00"`	Event start time (UTC)
`event_external_id_sportsdataio`	Event	No	String	`"19449"`	SportsDataIO ID
`event_external_id_sportradar`	Event	No	String	`"5848514c-..."`	Sportradar ID
`instrument_rules`	Instrument	Yes	String	`"Who will win..."`	Instrument-specific rules
`participant_type`	Participant	Yes	String	`"team"`	Type: team, player, nominee, etc.
`long_participant_id`	Participant	Yes	String	`"nfl-ne"`	Long side participant ID
`long_participant_name`	Participant	Yes	String	`"New England"`	Long side display name
`short_participant_id`	Participant	Yes	String	`"nfl-den"`	Short side participant ID
`short_participant_name`	Participant	Yes	String	`"Denver"`	Short side display name
`outcome_type`	Outcome	Yes	String	`"moneyline"`	Outcome type
`outcome_strike`	Outcome	Yes	String	`"ne"`	Strike value (participant abbreviation for moneyline, numeric for spreads/totals)

Attributes vs Metadata vs Event Attributes

Attributes contain trading and settlement parameters:

tick_size - Minimum price increment
minimum_trade_qty - Minimum order size
price_limit - Price bounds (low, high, low_set, high_set)
expiration_date - Contract expiration
expiration_time - Settlement time
last_trade_date - Final trading day
last_trade_time - Final trading time
base_currency - Settlement currency
clearing_house - Clearing organization
cfi_code - Classification of Financial Instruments code
settlement_price_logic - Settlement logic type
trade_day_roll_schedule - Trading day rollover schedule

Metadata contains descriptive and reference information:

cftc_instrument_id - CFTC registered instrument identifier
clearing_sym - Clearing symbol prefix
Event details (category, series, participants)
Resolution rules
External data provider IDs
Display names and formatting

Event Attributes contain event-specific trading parameters:

position_accountability_value - Position limit threshold
payout_value - Contract payout amount
question - Human-readable question
event_display_name - Formatted display name for the event
event_id - Event identifier
strike_value - Strike value for the outcome
evaluation_type - Comparison operator for resolution
strike_unit - Unit type for strike (string, decimal)
calculation_method - Settlement calculation method
time_specifier - Date for event occurrence

External Data Provider IDs

External IDs enable integration with third-party data sources: event_external_id_sportsdataio

SportsDataIO event identifier
Used for real-time scores and statistics
Example: "19449"

event_external_id_sportradar

Sportradar event identifier (UUID format)
Used for official data feeds and settlement
Example: "5848514c-3977-4aa3-9db0-94ed5d0ebb34"

These IDs allow automated resolution based on official data provider results.

Common Query Patterns

Use metadata fields to filter and find specific instruments:

Filter by Series

Find all NFL instruments:

metadata.event_series = "nfl"

Find all NBA instruments:

metadata.event_series = "nba"

Filter by Product Type

Find all moneyline contracts:

metadata.outcome_type = "moneyline"

Find all spread contracts:

metadata.outcome_type = "spread"

Filter by Participant

Find all instruments involving New England:

metadata.long_participant_id = "nfl-ne" OR metadata.short_participant_id = "nfl-ne"

Filter by Event

Find all instruments for a specific game:

metadata.event_id = "nfl-ne-den-2026-01-25"

Combined Filters

Find all NFL moneyline contracts:

metadata.event_series = "nfl" AND metadata.outcome_type = "moneyline"

Find all spread contracts with New England:

metadata.outcome_type = "spread" AND
(metadata.long_participant_id = "nfl-ne" OR metadata.short_participant_id = "nfl-ne")

Overview

Market Structure

Fees & Incentives

Regulatory Reporting

Data Structures

Frequently Asked Questions

Complete Hierarchy

Event ID Format

Instrument ID Format

Participant ID Format

Participant Lookup API

Uniqueness Rules

Multi-Product Events

Soccer Example with 3-Way Markets

Complete Metadata Reference

Attributes vs Metadata vs Event Attributes

External Data Provider IDs

Common Query Patterns

Filter by Series

Filter by Product Type

Filter by Participant

Filter by Event

Combined Filters

Overview

Market Structure

Fees & Incentives

Regulatory Reporting

Data Structures

Frequently Asked Questions

​Complete Hierarchy

​Event ID Format

​Instrument ID Format

​Participant ID Format

​Participant Lookup API

​Uniqueness Rules

​Multi-Product Events

​Soccer Example with 3-Way Markets

​Complete Metadata Reference

​Attributes vs Metadata vs Event Attributes

​External Data Provider IDs

​Common Query Patterns

​Filter by Series

​Filter by Product Type

​Filter by Participant

​Filter by Event

​Combined Filters

Complete Hierarchy

Event ID Format

Instrument ID Format

Participant ID Format

Participant Lookup API

Uniqueness Rules

Multi-Product Events

Soccer Example with 3-Way Markets

Complete Metadata Reference

Attributes vs Metadata vs Event Attributes

External Data Provider IDs

Common Query Patterns

Filter by Series

Filter by Product Type

Filter by Participant

Filter by Event

Combined Filters