After splitting from Karatbars and his partner in Karatbars,Harald Seiz (who started a competing project V999),Josip Heit and Alexandru Cocindau started the G999 project on top of Gold Standard Bank. G999 seems to be a direct fork of PIVX,and much of its documentation seems to correlate to a previous project called BitcoinPOS.
G999 has its roots in Karatbars,and as such is related to Karatbars,Freebay,GSB and V999
From its marketing material: G999 is a peer-to-peer electronic cash system that aims to become sound global money with fast payments, micro fees, a new generation of communication, and high transaction capacity.