The gang confronted and argued with the 41-year-old at about 12.50pm on Saturday near Niddry Road, Winchburgh.
They then attacked him from behind inflicting a number of wounds to his head, shoulder, hands and legs.
He was able to flee the suspects and returned home before phoning paramedics.
Police are now urging anyone who can help with their inquiries to come forward.
Detective Constable Grant Ross from Livingston CID said: “The suspects seemed to have intentionally targeted the victim and then subjected him to a violent attack.
“At this time we don’t have a description of the group and we would ask anyone else who was in the area and witnessed this incident to contact police immediately.
“Similarly, any passing motorists who may have relevant dash-cam footage of the attack, or those responsible should also get in touch.”
Those with information can contact Livingston CID via 101 and quote incident number 1895 of the 13th October. Alternatively, an anonymous report can be made to the charity Crimestoppers on 0800 555 111.
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