Miki Woodie
I have ussumed here that you mean a Codemeter key.
ArchiCAD 10, 11 and 12 will run with a CodeMeter licence, provided that they have been updated to the latest hotfix for these versions (CodeMeter Enabler).
To download the CodeMeter enabler please visit this page:
http://www.graphisoft.com/support/archicad/downloads/CodeMeterEnabler.html
Projects saved in ArchiCAD 8 or 9 should be converted to ArchiCAD 10.