The company uses a roster of European agencies, with Beattie McGuinnness Bungay handling duties in the UK.
BSkyB announced last week that Discovery will be part of the initial package of channels available on Sky's new high-definition service at launch. The new channel will offer specially commissioned exclusive content.
Discovery expanded its digital TV offering recently, with the launch the lifestyle channel Discovery Real Time Extra. The channel, which is available on the Sky platform, is aimed at male viewers. It broadcasts new commissions as well as repeats of lifestyle programmes.
Real Time Extra is Discovery's tenth TV channel and the fourth in its lifestyle portfolio. Other Discovery channels include Animal Planet, Discovery Civilisation and Discovery Travel and Living.
A spokesman for Discovery denied it was reviewing its media arrangements.