Lord Peter Melchett or another representative of the organisation will have to stand before Lord Johnston in the Court of Session tomorrow after Shell returned to court in another round of legal action.
The captain of the Greenpeace ship Altair, which is shadowing the redundant platform as it is towed to its Atlantic grave, was also ordered by the judge to appear at the Edinburgh court on the same day. Jonathan Castle took part in an occupation of the Brent Spar in the North Sea earlier this year in protest at plans to dump the installation at sea.
He will have to make a court appearance to explain his failure to obey an earlier legal order requiring him to disclose to Shell the identities of those who took part in the on-board protest.
Mr Castle was also ordered to explain his intentions and give undertakings which the court may require over reports that Greenpeace was planning to use the Altair to interfere with the sinking of the Brent Spar.
Greenpeace has campaigned for the decommissioning of the 65,000-tonne oil installation on land but Shell, the platform operator, claims it would be four times more expensive than disposing of it at sea.
Shell, which has resorted to the courts on several occasions during the struggle over the Brent Spar, returned to the Court of Session yesterday to seek further orders.
If the firm succeeds in identifying those taking part in the protest, it will be able to move for further court orders restraining them from disrupting the dumping.