The courtroom isn't the friendliest environment, especially when one side is suing the other for plagiarism, and tempers definitely seem to be at a low boil in the ongoing lawsuit between Led Zeppelin and Mark Andes, the founding bassist of Spirit.

As previously reported, Andes filed suit on behalf of deceased Spirit founder Randy California, seeking to win a co-writing credit for California on Zeppelin's "Stairway to Heaven." A number of fans — and California himself — have long noted the similarities between the introductory portion of "Stairway" and the Spirit song "Taurus," and those parallels are at the crux of the court case that's been making its way through the system for more than a year and a half.

During that time, there have been multiple accusations of shenanigans on either side. The plaintiffs' lead attorney was admonished by a judge for his conduct in another case, after which Zeppelin's attorneys were foiled in their attempt to have the case thrown out on a jurisdiction technicality. After finally being granted a change in venue, the band issued a retort to the lawsuit in which they admitted "that Led Zeppelin has been called one of the greatest bands in history and its members were and are exceptionally talented, but otherwise deny each and every allegation contained in paragraph 11 of the First Amended Complaint."

Now, reports The Wrap, attorneys for California's estate are accusing Zeppelin's lawyers of wasting the court's time by trying to have the case thrown out on the grounds that his trust isn't valid — a tactic they've scornfully referred to as a "pure fishing expedition."

Calling Zeppelin's requests for IRS documentation proving the trust's validity "overly broad, vague, irrelevant, not calculated to lead to the discovery of relevant evidence, and unduly burdensome," California's attorneys have argued that "there is no evidence to cast even the slightest bit of shade on the validity of the Trust, nor have Defendants argued that there is any real reason to doubt the validity of the Trust."

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