Delaware’s Chancery Court has dismissed a derivative suit against the directors of Houston-based Plains All American Pipeline stemming from a costly oil spill off the California coast, but gave unitholders one more chance to bolster their complaint.

Vice Chancellor Tamika Montgomery-Reeves ruled Thursday that the complaint from investor Inter-Marketing Group USA failed to establish demand futility by alleging that a majority of the Plains board likely faced personal liability in connection with the spill. However, Montgomery-Reeves said the plaintiffs could benefit from additional information resulting from criminal convictions in California, and granted Inter-Marketing leave to amend the complaint based on recent developments.