	Ref	Id	Element Name	Req	Type	Min/Max	Usage
	TRN01	481	Trace Type Code Description: Code identifying which transaction is being referenced	M	ID	1/2	Required

Code

Name

Current Transaction Trace Numbers

The term “Current Transaction Trace Number” refers to the trace number assigned by the creator of the 278 response transaction (the UMO).

Referenced Transaction Trace Numbers

The term “Referenced Transaction Trace Number” refers to the trace number originally sent in the 278 request transaction.

TRN02	127	Reference Identification Description: Reference information as defined for a particular Transaction Set or as specified by the Reference Identification Qualifier Industry: Patient Event Tracking Number	M	AN	1/30	Required
TRN03	509	Originating Company Identifier Description: A unique identifier designating the company initiating the funds transfer instructions. The first character is one-digit ANSI identification code designation (ICD) followed by the nine-digit identification number which may be an IRS employer identification number (EIN), data universal numbering system (DUNS), or a user assigned number; the ICD for an EIN is 1, DUNS is 3, user assigned number is 9 Industry: Trace Assigning Entity Identifier Use this element to identify the organization that assigned this trace number. If TRN01 is "2", this is the value received in the original 278 request transaction. If TRN01 is "1", use this information to identify the UMO organization that assigned this trace number. The first position must be either a "1" if an EIN is used, a "3" if a DUNS is used or a "9" if a user assigned identifier is used.	O	AN	10/10	Required
TRN04	127	Reference Identification Description: Reference information as defined for a particular Transaction Set or as specified by the Reference Identification Qualifier Industry: Trace Assigning Entity Additional Identifier Use this information if necessary to further identify a specific component, such as a specific division or group, of the company identified in the previous data element (TRN03).	O	AN	1/30	Situational

Notes:

1. Any trace numbers provided at this level on the request must be returned by the UMO at this level of the 278 response.
2. The UMO can assign a trace number to this patient event for tracking purposes.
3. If the 278 request transaction passes through more than one clearinghouse, the second (and subsequent) clearinghouse may choose one of the following options:
If the second or subsequent clearinghouse needs to assign their own TRN segment they may replace the received TRN segment belonging to the sending clearinghouse with their own TRN segment. Upon returning a 278 response to the sending clearinghouse, they must remove their TRN segment and replace it with the sending clearinghouse’s TRN segment.
If the second or subsequent clearinghouse does not need to assign their own TRN segment, they should merely pass all TRN segments received in the 278 request in the 278 response transaction.
4. If the 278 request passes through a clearinghouse that adds their own TRN in addition to a requester TRN, the clearinghouse will receive a response from the UMO containing two TRN segments that contain the value “2" (Referenced Transaction Trace Number) in TRN01. If the UMO has assigned a TRN, the UMO’s TRN will contain the value ”1" (Current Transaction Trace Number) in TRN01. If the clearinghouse chooses to pass their own TRN values to the requester, the clearinghouse must change the value in their TRN01 to “1" because, from the requester’s perspective, this is not a referenced transaction trace number.

Example:

TRN*2*2001042801*9012345678*CARDIOLOGY~

1.	TRN02 provides unique identification for the transaction.
2.	TRN03 identifies an organization.
3.	TRN04 identifies a further subdivision within the organization.