# FIX 4.4: Enumerations of MDEntryType

**URL:** <https://forum.fixtrading.org/t/fix-4-4-enumerations-of-mdentrytype/16840>\
**Category:** General Q&A\
**Tags:** general-qa, help-wanted\
**Created:** [November 8, 2022, 3:50pm UTC](https://forum.fixtrading.org/t/fix-4-4-enumerations-of-mdentrytype/16840 "2022-11-08T15:50:48Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![alexandershukaev](https://avatars.discourse-cdn.com/v4/letter/a/258eb7/32.png) [@alexandershukaev](https://forum.fixtrading.org/u/alexandershukaev)\
**Post date:** [November 8, 2022, 3:50pm UTC](https://forum.fixtrading.org/t/fix-4-4-enumerations-of-mdentrytype/16840/1 "2022-11-08T15:50:49Z")

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Looking at unified `FixRepository.xml`, I notice that in FIX 4.4 `MDEntryType` is missing many enumerations, e.g. `J` (Empty Book). Compare that to [fiximate.fixtrading.org](https://fiximate.fixtrading.org/). At the same time, if I look into FIX 5.0 (also in `FixRepository.xml`), the definition of `MDEntryType` does contain all the missing enumerations and all of them are in fact marked with `added="FIX.4.4"`. Is this a bug in `FixRepository.xml` or am I missing something? Thanks.

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**Author:** ![gtcpm](https://avatars.discourse-cdn.com/v4/letter/g/b2d939/32.png) [@gtcpm](https://forum.fixtrading.org/u/gtcpm)\
**Post date:** [November 8, 2022, 4:02pm UTC](https://forum.fixtrading.org/t/fix-4-4-enumerations-of-mdentrytype/16840/2 "2022-11-08T16:02:35Z")

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MDEntryType(269)=J (Empty Book) was added with Extension Pack EP7. The process of EPs was started AFTER FIX 4.4 but only as of EP98, each EP was immediately published. Before that, EPs were rolled into the next version of FIX, in the case of EP7 that was FIX 5.0.

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**Author:** ![alexandershukaev](https://avatars.discourse-cdn.com/v4/letter/a/258eb7/32.png) [@alexandershukaev](https://forum.fixtrading.org/u/alexandershukaev)\
**Post date:** [November 8, 2022, 8:42pm UTC](https://forum.fixtrading.org/t/fix-4-4-enumerations-of-mdentrytype/16840/3 "2022-11-08T20:42:40Z")

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Sorry, not really understanding the answer. I’m not sure what EPs are, perhaps some upgrades/revisions. The counterparty runs on FIX 4.4 and they expect `J` to be in the protocol. Since the XML itself already indicates that it was `added="FIX.4.4"` but somehow in FIX 5.0 section, is it valid to monkey-patch that XML and backfill these missing constants into FIX 4.4 section? Thanks.

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<div class="post-metadata">

**Author:** ![gtcpm](https://avatars.discourse-cdn.com/v4/letter/g/b2d939/32.png) [@gtcpm](https://forum.fixtrading.org/u/gtcpm)\
**Post date:** [November 8, 2022, 8:46pm UTC](https://forum.fixtrading.org/t/fix-4-4-enumerations-of-mdentrytype/16840/4 "2022-11-08T20:46:41Z")

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> [@alexandershukaev](#):
>
> The counterparty runs on FIX 4.4 and they expect `J` to be in the protocol.

The counterparty cannot expect “J” to be supported because it was not supported with FIX 4.4 when that version was released. Extension Packs extend the capabilities of a base version and are an integral part of the next version. The correct pedigree is not

> added=“FIX.4.4”

but

> added=“FIX.4.4” addedEP=“7”.

Extension Packs are a mandatory part of the version information, you cannot omit that.