Does an assignee have standing to sue on an assignment?

"An assignment carries with it all the rights of the assignor. [Citations.] 'The assignment merely transfers the interest of the assignor. The assignee "stands in the shoes" of the assignor, taking his rights and remedies, subject to any defenses which the obligor has against the assignor prior to notice of the assignment.' [Citation.] Once a claim has been assigned, the assignee is the owner and has the right to sue on it. [Citation.] In fact, once the transfer has been made, the assignor lacks standing to sue on the claim." (Johnson v. County of Fresno (2003) 111 Cal.App.4th 1087, 1096.)