Interpreting CME Grain Serial Option Expiration Rules

Summary

The document compares CME expiration language for serial options on several grain contracts. Most examples specify the last Friday that falls at least two business days before month-end, with a fallback to the preceding business day if that Friday is not a business day. The Soybean specification instead refers to the month preceding the option month, prompting the author to ask whether that wording means a different expiration date or describes the same holiday adjustment less clearly.

The evidence is a comparison of contract specification wording, including Soybean Meal and Soybean Oil alongside Soybeans, and a search for historical dates where the expected Friday fell on a holiday. The author identifies December 2010 and December 2015 as cases without located expiration data. The document poses an unresolved contract-calendar interpretation question; it does not establish CME’s intended reading or provide an authoritative answer, so the specifications or exchange calendar would need to be checked directly.

Key ideas

• CME grain serial option specifications use similar but not identical wording for expiration timing.
• Several contracts describe a Friday before month-end and a fallback when that Friday is not a business day.
• Soybean options refer to the month preceding the option month, creating ambiguity about the intended date.
• The document does not resolve the interpretation or provide historical confirmation for the cited holiday cases.

Tags

# How to interpret CME's specification regarding grains options expirations?


# How to interpret CME's specification regarding grains options expirations?












Looking at the contract specifications for Soybean Meal and Soybean Oil (same for Corn, Wheat, and other major stuff I checked) serial options on CME I see the following expiration rule:

> the last Friday which precedes by at least two business days the last business day of the calendar month... If such Friday is not a business day, then the last day of trading in such option shall be the business day prior to such Friday.

However, for Soybeans, it states:

> The last Friday which precedes by at least two business days the last business day of the month preceding the option month.

This is a bit confusing as it may suggest that expiration should be transferred to the previous Friday week back, rather than one day back (in case of holiday). As it is now, it states that the expiration is Friday (and not any other day would do). Since all other contract specifications have matching descriptions, I find it strange that this one is different. So, is it merely a slightly clumsy statement of the same rule, or the expiration dates for Soybean options are different for some reason?

I was unable to find expiration data for months when the would-be-expiration falls on holiday, which are December 2010 and 2015.

Shown in full with attribution under the source's licence. Licence: CC BY-SA 4.0 (Stack Exchange)

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.