Kubica failed to see the chequered flag for the first time in Sochi, as Williams called him into the pits shortly after team-mate George Russell crashed out.
Russell had suffered brake failure behind the VSC, going straight on into the barriers, and it had been reported in the immediate aftermath that Kubica had been taken off the track to avoid suffering a similar incident.
However, post-race the team revealed that Kubica had in fact been retired in a bid to avoid damaging parts on his car.
“We opted to retire Robert soon afterwards in order to conserve parts ahead of the intense flyaway races which end the season,” chief race engineer Dave Robson said.
Orlen were reported to have put £10million behind Kubica as he secured a race deal at Williams in 2019, completing a stunning comeback to the sport after recovering from life-altering injuries sustained in a 2011 rally crash.
And company spokesperson Joanna Zakrzewska posted on Twitter that Orlen were seeking answers.
She wrote: “Following the retirement of Robert Kubica from Sunday’s Russian GP, we have officially asked the ROKiT Williams Racing team for an explanation. Based on that we will take actions to enforce contractual obligations.”