A number of London-based shops have been approached with a communications brief.
Digital advertising is understood to be the lead medium, with press, radio and direct marketing also being considered to support the campaign.
Green Inventions advises on how to become carbon neutral by calculating annual CO2 emissions. It then plants trees across UK rural sites.
Companies take a 12-month subscription to the service, during which time they are kept up to date on the quantity of trees being planted and their growing progress.
The search comes as carbon offsetting grows in popularity with media companies. Earlier this year, ZenithOptimedia held talks with The CarbonNeutral Company about formulating a "green index" to advise about the costs of carbon offsetting ad campaigns.
The outdoor specialist IPM also invited its clients to offset carbon emissions by adding the cost to outdoor budgets.
Green Inventions had not returned calls as Campaign went to press.