Below is a list of Acronyms and their meaning for ITIN RTS.The Acronym/Meaning are as follows:AA (Acceptance Agent)ADD (Address)ALT CONT (Alternate Contact)APPL (Form 13551 Application)ATTY (Attorney)BALDUE (Balance Due)BEARS (Business Entitlement Access Request System)BI (Background Investigation)BKPT (Bankruptcy)CAA (Certifying Acceptance Agent)CAA DUT (Certifying Acceptance Agent Document Upload Tool)CPA Certified Public Accountant)DOB (Date of Birth)EA (Enrolled Agent)ECDS (External Customer Data Store)EFIN (Electronic Filing Number)ERO Electronic Return Originator)ESAM (External Services Authorization Management)EUP (Employee Users Portal)F# (Form Number)FPC (Fingerprint Card)FTF (Failure to File)GC (Green Card)ILO (In Lieu of)INCOMPL (Incomplete)INDIV (Individual)IPS (ITIN Policy Section)LMTCBW (Left Message to Call Back with (name))LTR (Letter)MR (Missing Return)OPR (Office of Professional Responsibility)POPS (Proof of Professional Status)PRIM CONT (Primary ContactPTIN (Preparer's Tax Identification NumberRECD (Received)REJ (Rejected)RP (Responsible Party)RPO (Return Preparer's Office)RUP (Registered User Portal)SUBST4 (Substitute for Return)SIG (signature)SOS/RP (Submitted Outside Renewal Period)STRUC (Structure)SUIT (Suitability)SUSP (Suspended)TCC-B (Tax Compliance Check - Business)TCC-I (Tax Compliance Check - Individual)TERM (Terminated)UPD (Updated)UTC (unable to Contact)