(concurring).
I agree with the holding of the court and its reasoning and write separately only to express my belief that the fundamental principle of equity is an additional and compelling ground for denying respondents the relief they seek.
Having accepted the $10 million financial assistance package from the City in 1985 in the form of tax increment financing bonds, a subsidy that was hardly reluctantly received by the developers, it comes with ill-grace for respondents to now complain that almost 15 years ago the assessor failed to do his job when certifying the property values as a part of the financing package. Therefore, I would add to the court’s rationale for upholding the assessment agreement that by accepting its benefits for almost ten years, respondents, through their predecessor in interest, have waived any defect in the statutory certification- process set forth in Minn.Stat. § 273.76, subd. 8 (1984), and are estopped from denying the certification’s validity by the passage of time and acceptance of ben*878efits of the agreement. See Ostraum v. City of Minneapolis, 236 Minn. 378, 383, 53 N.W.2d 119, 121-22 (1952).