[ULPIANUS libro septuagensimo ad edictum. ] §6.1.25.prIs qui se optulit rei defensioni sine causa, cum non possideret nec dolo fecisset, quo minus possideret: si actor ignoret, non est absoluendus, ut Marcellus ait: quae sententia uera est.
[ULPIAN, in the seventieth book on the Edict.] A person who has presented himself to defend a thing without cause, when he was not in possession and had not acted with fraud to avoid possession, if the plaintiff is ignorant of this, is not to be absolved, as Marcellus says; and this opinion is correct.
sed hoc post litem contestatam: ceterum ante iudicium acceptum non decipit actorem qui se negat possidere, cum uere non possideret: nec uidetur se liti optulisse qui discessit.
But this applies after the joinder of issue (litis contestatio); on the other hand, before the trial is accepted (iudicium acceptum), one who denies that he is in possession when he really is not does not deceive the plaintiff, nor is one who has withdrawn deemed to have presented himself for the lawsuit.