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Learn how we engage with policy makers to ensure safe, reliable, and affordable energy for the future as demand continues to grow.

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API 1509 Documents

Products + Services / Engine Oil (EOLCS) / Documents / API 1509 Documents

API 1509 describes the voluntary API Engine Oil Licensing and Certification System (EOLCS) and explains to marketers how different API marks are licensed and displayed for the consumer. The current edition of API 1509 is now available and can be downloaded in pdf format.