The Austrian forward is understood to be the subject of a £19.7million bid from an unnamed Chinese Super League club.
It comes just seven months after he asked to leave the London Stadium to make a big-money move to the Far East in January.
West Ham ultimately rejected a £35m bid from a Chinese club and he ended up signing a bumper contract extension.
But, speaking exclusively to talkSPORT, Sheringham believes it may be time to cash in, if the player again asks to leave.
“It all depends on Marko’s attitude,” the former Hammers striker told Ian Abrahams.
“Does he want to leave? Is he seeing himself going to China? Does he want to play for West Ham on the money he’s on? Is he going keep constantly having his head turned? I don’t know.
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