Which airplanes are exempt from Europe's 2015 CPDLC (Link 2000+) requirement?
The European Commission has published the Commission Implementing Decision of 9.12.2011
on exemptions under Article 14 of Commission Regulation (EC) N° 29/2009 (the CPDLC rule)

It contains the following table of aircraft that are permanently exempted from the CPDLC implementing rule.

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║           Model            ║  ICAO Id   ║ Marketing Name ║
╠════════════════════════════╬════════════╬════════════════╣
║ Airbus A318 - 112          ║ A318       ║ A318           ║
║ Airbus ACJ - 319           ║ A319       ║ ACJ 319        ║
║ Airbus ACJ - 320           ║ A320       ║ ACJ 320        ║
║ Airbus A330 – 200/300      ║ A332/A333  ║ A330           ║
║ Airbus A340 – 200/300      ║ A342/A343/ ║ A340           ║
║              /500/600      ║ A345/A346  ║                ║
║ British Aeropace AVRO      ║ RJ1H       ║ AVRO RJ        ║
║     RJ100                  ║            ║                ║
║ Dassault Falcon 10 and     ║ FA10       ║ Falcon 10      ║
║     Falcon 100             ║            ║                ║
║ Dassault Fan Jet Falcon    ║ FA20       ║ Falcon 20      ║
║     Basic and              ║            ║                ║
║     Serie C/D/E/F/G        ║            ║                ║
║ Dassault Mystère-Falcon    ║ FA20       ║ Falcon 20      ║
║     200, 20GF and 20-      ║            ║                ║
║     C5/D5/E5/F5            ║            ║                ║
║ Dassault Falcon 50EX and   ║ FA50       ║ Falcon 50      ║
║     Mystère Falcon 50      ║            ║                ║
║ Dassault Falcon 900, 900B, ║ F900       ║ Falcon 900     ║
║     900C and 900 EX        ║            ║                ║
║ Dassault Falcon 2000       ║ F2TH       ║ Falcon 2000    ║
║     and 2000EX             ║            ║                ║
║ Gulfstream GIV             ║ GLF4       ║ Gulfstream IV  ║
║     and GIV-SP             ║            ║                ║
║ Gulfstream G300            ║ GLF4       ║ Gulfstream 300 ║
║ Gulfstream G400            ║ GLF4       ║ Gulfstream 400 ║
║ Gulfstream GV              ║ GLF5       ║ Gulfstream V   ║
║ McDonnell Douglas MD11-F   ║ MD11       ║ MD-11          ║
║      and MD11-CF           ║            ║                ║
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