What is the test for a motion to set aside or annul a judgment that was procured by extrinsic fraud?

[92 Cal.App.3d 553] Although appellants do not speak specifically in terms of extrinsic fraud in their brief, it is clear that their second motion was based primarily on the power of the court to grant equitable relief from a judgment procured by extrinsic fraud. However, the alleged fraud consisting of "deliberate, intentional misrepresentations, untruths, half truths, and deceitfully misleading affidavits, arguments and declarations" ² on the part of respondents is clearly what courts have consistently characterized an intrinsic fraud, not extrinsic. The rule is classically stated in Pico v. Cohn (1891) 91 Cal. 129, 133-134, 25 P. 970, 971-972:

". . . That a former judgment or decree may be set aside and annulled for some frauds there can be no question, but it must be a fraud extrinsic or collateral to the questions examined and determined in the action. And we think it is settled beyond controversy that a decree will not be vacated merely because it was obtained by forged documents or perjured testimony. The reason of this rule is that there must be an end of litigation; and when parties have once submitted a matter, or have had the opportunity of submitting it, for investigation and determination, and when they have exhausted every means for reviewing such determination in the same proceeding, it must be regarded as final and conclusive, unless it can be shown that the jurisdiction of the court has been imposed upon, or that the prevailing party, by some extrinsic or collateral fraud, has prevented a fair submission of the controversy. What, then, is an extrinsic or collateral fraud, within the meaning of this rule? Among the instances given in the books are such as these: Keeping the unsuccessful party away from the court by a false promise of a compromise, or purposely keeping him in ignorance of the suit; or, where an attorney fraudulently pretends to represent a party, and connives at his defeat or, being regularly employed, corruptly sells out his client's interest. (United States v. Throckmorton, 98 U.S. 65, 66, (25 L.Ed. 93) and authorities cited.)