Article 515 of the Civil Procedure Law states in a different statement regarding the liability of the plaintiff against the defendant for litigation damages compared to the liability of the defendant against the plaintiff: "... the defendant can also claim damages intentionally caused by the plaintiff with knowledge of being unjustified in the proceedings brought against him ..." This different and notable expression of the legislator needs to be investigated. In the same article regarding how to claim damages in the proceedings, it has been established the possibility of such a claim without submitting a petition during the proceedings. In articles 109 and 144 of that law, it is prescribed to obtain security from the plaintiff to compensate for the damages of the defendant's proceedings in fictitious lawsuits and in lawsuits of foreign nationals against of the Iranian defendant. The phrase "litigation fee" in these two articles and the silence of those articles regarding how to claim and compensate the defendant from the provision received from the plaintiff, has caused a debate and disagreement, which requires investigation and analysis in this field.