US Options Trade and Top of Book Quote

How to use it

Identify a contract by underlying, expiration, strike and call/put. Most options tick files carry no underlying/root column: the underlying comes from the file path or API identifier, so keep it alongside every row you land. Strikes and prices are plain decimals (not scaled). EventType is a bit field: low 4 bits message type, 16 cancel, 32 call, 64 NBBO, 128 buy/bid side. Check OCC special settlements before comparing prices across a corporate action.

Typical use

Options pricing, volatility, and flow research on US-listed equity and index options.

Limitations

Delivered as recorded from the source feed: AlgoSeek does not remove crossed or locked quotes, bad prints, or out-of-sequence packets unless contracted to. Consumers own cleaning. Contract identity per row = Ticker (option root/underlying, sample AAPL) + ExpirationDate + StrikePrice + CallPut; UnderSymbol repeats the underlying. No OSI/OCC symbol column exists; one could be built from these fields. StrikePrice (e.g. 192.5) and all option and underlying prices are plain decimals in dollars per share, not scaled by 1000; the contract multiplier is not in the file. EventType decoding verified on the sample: 33 = 32 call + 1 Trade; 1 = put Trade; NBBO bit is clear on trade rows and Side is blank. Bit 4 (16) would mark a cancelled prior trade; no cancel rows appear in the sample, but cancel conditions A, C, E, G exist in Conditions. LastNBBO* fields give the best bid/ask (with posting exchange) before the trade; List* fields give each exchange's own last bid/ask. In the sample the NBBO bid price always equals the List price at its exchange (100 of 100).

Coverage

Trades and top-of-book quotes from the 16 SEC-approved options exchanges via OPRA for options on equities, ETFs, ETNs and ADRs (guide); the product page says all listed US options contracts disseminated via OPRA. Start date not stated.

Usage constraints

• Licensed vendor data: never export raw rows to a tenant-local destination or include them verbatim in a public artifact; serve only through entitlement-checked platform reads.
• Do not treat the vendor's `Ticker` as a stable identity across time; join on an AlgoSeek security key (SecId or ASID, which are distinct) or the platform symbol mapping.

Known issues (18)

• Primary key is inferred; AlgoSeek's guide does not name one.
• Documentation discrepancyGuide field table orders EventType, Side, Action; the sample header orders EventType, Action, Side.
• Documentation discrepancyGuide Table 1 intro says the table is for the 'Options Trade Only data file' (copy-paste from the Trade Only guide).
• Documentation discrepancyGuide types EventType as 'string'; sample values are decimal integers rendered as text (1, 33).
• Documentation discrepancyGuide types UnderLastTradeSize as 'decimal'; every sample value is a whole number.
• Documentation discrepancyGuide describes UnderTotalTradeSize and UnderTotalTradeCount as the size and count of the last trade; sample values grow monotonically with time (609460 to 645508; 3616 to 4122), so they behave as cumulative running totals for the underlying.
• Documentation discrepancyGuide gives no code tables for UnderBidConditions, UnderAskConditions, UnderLastTradeConditions (sample: 8-character values like 00000001, 80000001, A0000201) or for the single-letter Under*Exchange codes (sample: Z, Q, X, P, U, V, N, D, J, Y); Table 2 covers options exchanges only.
• Documentation discrepancyNumber of elements in the List* columns varies by row (16 in 81 rows, 15 in 19 rows; AR is absent from the shorter lists) and exchange order differs from row to row.
• Documentation discrepancyListLastQuoteCondition equals ListLastBidCondition in all 100 sample rows and ListLastAskCondition in 99; the guide does not explain how it differs.
• Documentation discrepancyGuide intro says top-of-book quotes and all trades, but the sample (and page) contain only trade rows (Action 'T'); quote events are not rows.
• Documentation discrepancyProduct page says coverage includes all listed US options contracts; the guide scopes it to options on equities, ETFs, ETNs and ADRs.
• Documentation discrepancyGuide Table 3 (Action) adds HB = Heartbeat that does not appear in the other options guides; Table 7 still lists Heartbeat as not in use.
• Documentation discrepancyGuide intro says 16 options exchanges, but Table 2 lists 31 codes including FINRA, OPRA, SIAC, THOMSON and UNKNOWN.
• Documentation discrepancyGuide Table 6 says bits 0-3 are a '3-bit' message type, but bits 0-3 are 4 bits and Table 7 runs to value 11.
• Documentation discrepancyGuide Table 7 names message type 10 'UnderlyingValueSell' while Table 3 names the matching action 'UnderlyingValueSale'.
• Documentation discrepancyGuide Table 7 has no type 12 (Indicative); Table 3 lists action 'I' = Indicative Value and 'IN' = Invalid with no message-type value. The AlgoSeek decoder convention assigns 12 = Indicative.
• Documentation discrepancyGuide describes Quantity as 'Underlying asset quantity'; sample values (1..3444, quote sizes) behave as option contract counts.
• Documentation discrepancyGuide expands OPRA as 'Options Pricing Authority' while the product pages say 'Options Price Reporting Authority'.