I was perplexed by Judge Cindee F. Mayfield's repeated references to "derivate claims" in a recent unpublished opinion - JBB Investment Partners v. Fair, Cal. Ct. of Appeal Case No. No. A160098 (June 9, 2022).  Was this a typographical error or was Judge Mayfield's diction correct?

Although I was familiar with the noun, "derivate", I was unaware that it is also an adjective having the same meaning as "derivative".  Judge Mayfield's opinion informs us that the case involved, at least in part, an action under Section 800 of the California Corporations Code.  That statute governs actions "instituted or maintained in right of any domestic or foreign corporation".  These are commonly referred to as "derivative actions" but the statute does not denominate them as such.  Therefore, Judge Mayfield's diction is not inconsistent with the General Corporation Law.   It is also not without (unpublished) precedent.  See, e.g., Baharian-Mehr v. SGRL Investments, Inc., Cal. Ct. Appeal Case No. G047929 (March 10, 2014) ("The Plaintiff did not plead, nor did he prove the requirements to maintain a derivative action and did not meet the requirement under Corporations Code section 800(b)(2) to proceed with derivate claims.").

Both "derivate" and "derivative" are derived from the Latin words de and rivo, meaning from the stream.  The Romans combined these to form the verb derivare which means to lead off or transfer.