Implementing UCD? MISMO 3.4 is Less Disruptive Than You Think: Part 2


(Steve Acker is Owner/Consultant of Closergeist LLC, Roanoke, Va., which provides implementation guidance and services to clients in the mortgage and title industries. He can be reached at

Part 1 of this series discussed the need to remain current and support new versions of the MISMO Reference Model in implementations, while also maintaining the ability to implement specifications requiring an older version of MISMO. Fortunately, earlier data exchange specifications are often highly compatible with newer versions of the standard, and the Uniform Closing Dataset is no exception.

The UCD is an electronic file that allows the information contained within the Consumer Financial Protection Bureau’s Closing Disclosure form to be captured and transmitted in a standard, machine-readable format. Fannie Mae and Freddie Mac will require a UCD file, in the MISMO 3.3 format, for all loans they acquire beginning in Q3 2017.

A newer version of the standard, MISMO 3.4, will soon be required for other data reporting requirements, such as the GSEs’ Uniform Loan Application Dataset and the CFPB’s Home Mortgage Disclosure Act.

As was discussed in Part 1, an important first step in planning an implementation approach that supports multiple versions of MISMO is to examine data specifications that must conform to earlier versions and determine what specific data requirements, if any, are invalidated by later versions.

This article will use the UCD as a case study to demonstrate the three steps involved in identifying and working with specific pieces of information that must be handled by systems in different ways, depending on the MISMO version:

–Identify points of incompatibility

–Determine how to represent incompatible data points in alternate MISMO versions

–Produce valid XML files for each MISMO version

This process can be applied to any specification as a way to gauge compatibility and account for differences when adding support for a newer version of MISMO.

Identify Points of Incompatibility
Identifying points of incompatibility in a specification consists of answering the following questions for each distinct piece of information, or data point:

–In the alternate MISMO version, is the data point’s XPath, or specific location within the MISMO XML file, still valid?

–Does the data point still exist in the expected spot, and with the same name?

–Do all allowable enumerated values for a particular data point exist in the alternate MISMO version (when applicable)? (Enumerated values are a choice of values, similar to a pick list or drop-down list in an application).

To determine areas of the UCD specification that are not compatible with MISMO 3.4, these questions must be answered in turn for each data point listed in the UCD Delivery Specification, Appendix I.

As an example, consider the AddressUnitDesignatorType data point, which is required when a subject property address contains a unit number, such as 123 Elm St., Apt. 104. AddressUnitDesignatorType describes the nature of the unit designator–whether it is an apartment number, suite number, or some other type.

Appendix I of the UCD specification lists the following three requirements for representing this data point within a MISMO 3.3 file:


–MISMO v3.3.0 Data Point Name:

–UCD Supported Enumerations (choose one):
Apartment, Basement, Building, Condo, Department, Floor, Front, Hanger, Key, Lobby, Lot, Lower, Office, Penthouse, Pier, Rear, Room, Side, Space, Stop, Suite, Trailer, Unit, Upper

We can use this information to examine MISMO 3.4 and answer the three questions from above:


–In MISMO 3.4, does the data point AddressUnitDesignatorType still exist at that location, with the same name? The answer is yes.

–Do all of the UCD Supported Enumerations listed above exist in MISMO 3.4? The answer is no. The value “Hanger” does not exist in MISMO 3.4, but “Hangar” (note the corrected spelling) does exist.

This exercise tells us that the AddressUnitDesignatorType data point must use different enumerated values in MISMO 3.3 (UCD) and MISMO 3.4 when the unit in question is an airplane hangar. Fortunately, this is not a common lending scenario.

Analyzing the entire UCD specification reveals very few spots where the newer MISMO 3.4 no longer exactly supports UCD requirements. In fact, the only differences are four enumerated values that are allowed by the UCD, but went away in MISMO 3.4:

–AddressUnitDesignatorType: Hanger

–AssetType: SecuredBorrowedFundsNotDeposited

–FeeType: 203kArchitecturalAndEngineeringFee

–FeeType: PropertyTaxStatusResearchFee

Determine How to Represent Incompatible Data Points in Alternate MISMO Versions
When systems must support multiple versions of MISMO, special care must be taken when handling data points that are known to have incompatibilities. For these data points, applications that create or consume MISMO files will need to work differently depending upon MISMO version.

In some cases, a data point might simply have moved to a new location, or XPath, in the alternate MISMO version. A quick search of the MISMO Logical Data Dictionary (LDD) will usually indicate if this is the case. If so, applications working with the alternate version of MISMO can simply use the new XPath when creating or reading the data point in question.

Other times, a data point might have been renamed or eliminated. In these cases, searching the LDD for text around the definition, or meaning, of the data point, will often reveal a suitable alternative.

In some instances, no suitable data point exists in the alternate MISMO version. As a fallback, MISMO provides the capability to place custom information in files using a mechanism known as an extension.

Handling enumerated values that are valid for the UCD or some other specification, but not supported in an alternate MISMO version, is a simpler task. A good practice is first to search the other available enumerated values for a data point to see if another option makes sense. In the case of the disappearing “Hanger” enumeration mentioned previously, a quick scan in the LDD of other possible enumerated values for the AddressUnitDesignatorType reveals “Hangar” (different spelling).

In some cases, no immediate option may be apparent for mapping an enumerated value that has gone away. Using an enumerated value of Other and filling in the corresponding OtherDescription data point is usually an allowable workaround. Using a FeeType of “Other” and a FeeTypeOtherDescription of “Alligator Removal Fee” is an oft-cited real world example.

Produce Valid XML files for Each MISMO Version
Once all points of incompatibility within the UCD or other specifications have been identified and handled appropriately, supporting multiple versions of the MISMO standards becomes a much easier proposition. With the UCD serving as a catalyst for many organizations to implement MISMO 3.3, it is reassuring to know that adding MISMO 3.4 support for future needs will not provide much disruption.

MISMO® is the voluntary standards development body for the mortgage industry. Voluntary use of MISMO standards reduces processing costs, increases transparency and boosts investor confidence in mortgages as an asset class, while creating cost savings for the consumer. For more information, visit