The singer, who has twins, Max and Emme, five, with ex-wife Jennifer Lopez, is expected to pop the question to his 22-year-old girlfriend and has asked her father, Topshop owner Philip Green, for permission, reported Grazia magazine.
"Marc is incredibly respectful of Philip and Chloe's mother Tina, and is already treated as one of the family. Marc is by far Sir Philip's favourite boyfriend of Chloe's. Their relationship has his blessing," a source said.
The couple first got together in February but experienced a brief bump in the road in April. However, they quickly reunited and were spotted holidaying with Chloe's family in the south of France in July. Marc and Chloe also recently enjoyed a couples retreat to Italy.
The marriage would be the third for Marc, who was wed to Jennifer between 2004 and 2012, and was previously married to Dayanara Torres between 2000 and 2004.