Preserve the economic identity
Equity option integration becomes more difficult when a contract changes or when different providers name the same instrument differently. Use an internal identifier, a source-aware alias table and versioned contract definitions. This preserves historical meaning while allowing the current interface to use a familiar display symbol.
An adjustment is not just a new ticker
Corporate actions may change the security or quantity represented by an option. The Options Industry Council explains why the specific adjustment terms matter. Treat the actual notice as the basis for your mapping, and preserve its effective date and source reference. Do not generalize a conversion rule from a news headline.
Separate the two multipliers people confuse
The amount used to convert a premium quote into a contract price is not necessarily the number of shares delivered. Use separate premium and deliverable fields. A basket representation gives your schema room for securities and cash components without forcing them into a single number whose interpretation changes from record to record.
Version history is part of the product
Store both when terms apply and when your application learned them. Those timestamps answer different research questions. An active chain can filter adjusted series while an archival view preserves them. Make the filter explicit; an excluded record should not look like evidence that the contract never existed.
