---
title: "GM1 to AMC4 ATS.OR.205(a)(2) Safety assessment and assurance of changes to the functional system — SPECIFIC REQUIREMENTS FOR PROVIDERS OF AIR TRAFFIC SERVICES, ATM/ANS · Avioverse"
description: "ASSURANCE — SOFTWARE ASSURANCE PROCESS In reference to the terms ‘correct and complete software verification’, ‘software timing performances’, ‘software…"
url: "https://avioverse.aero/regulations/easa/atm-ans/part-ats/subpart-a/gm1-to-amc4-ats-or-205-a-2-safety-assessment-and-assurance-of-changes-to-the"
---

# GM1 to AMC4 ATS.OR.205(a)(2) Safety assessment and assurance of changes to the functional system

SPECIFIC REQUIREMENTS FOR PROVIDERS OF AIR TRAFFIC SERVICES · Regulation (EU) 2017/373 · EAR revision 12 Mar 2025

GM Guidance material

## GM1 to AMC4 ATS.OR.205(a)(2) Safety assessment and assurance of changes to the functional system

ASSURANCE — SOFTWARE ASSURANCE PROCESS

In reference to the terms ‘correct and complete software verification’, ‘software timing performances’, ‘software capacity’, ‘software accuracy’, ‘software resource usage’, ‘software robustness’, ‘overload tolerance’, ‘software life cycle data’ and ‘COTS’, please refer to GM1 to AMC6 ATM/ANS.OR.C.005(a)(2) ‘Safety support assessment and assurance of changes to the functional system’.

GM — Regulation (EU) 2017/373 · ED Decision 2019/022/R · ATM/ANS Easy Access Rules · EAR revision 12 Mar 2025

[All rules in SUBPART A — ADDITIONAL ORGANISATION REQUIREMENTS FOR PROVIDERS OF AIR TRAFFIC SERVICES (ATS.OR)](https://avioverse.aero/regulations/easa/atm-ans/part-ats/subpart-a)

Consolidated from the EASA Easy Access Rules (revision 12 Mar 2025, extracted 13 Oct 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.