Rumours of a rift began to circulate back in August, though the couple later branded the claims "completely false" and "ridiculous".
Friends of the actors also dismissed talk of their separation as "total bulls**t".
Insiders have now told TMZ that the pair clashed over how best to manage the careers of Jaden and Willow, with the Men In Black star reportedly "pushing more for full-blown stardom" as Pinkett Smith called for their workload to be reduced.
The same sources insist that Will and Jada's 13-year marriage is still going strong and the couple are feeling "wonderful" now.
Reports of their split emerged alongside speculation that Pinkett Smith had an affair with Jennifer Lopez's ex-husband Marc Anthony, though these stories were also denied.