When the Kyoto protocol was initiated in 1997, it was agreed that industrialized countries would sign and those countries that decide to follow through will ratify the protocol. At that time, the member states that ratified were grouped into two categories as Annex 1 and Non-Annex 1 countries. The developed countries are Annex 1 and the developing countries are Non-Annex 1.
As implementation of the protocol would require some economical setbacks for a country, it was agreed that the protocol should not be made legally binding for the developing countries. In fact, the non-annex 1 nations have the liberty to increase their greenhouse gases emissions without penalty. China is classified under developing nation, so it was granted exception from the stringent targets of the Kyoto protocol.
There is a wide spread criticism against this stand of the UNFCCC, as many opine that developing countries such as India and China contribute to major greenhouse gases emissions in the world.