N.J. Stat. § 54:5-79
The title of a purchaser at a sale shall cease and determine and the certificate of sale except as otherwise provided in this section shall be void at the expiration of 20 years from the date of the sale, unless the purchaser, his heirs or assigns shall, before the expiration of that term, foreclose the right to redeem it by notice or by a civil action in the nature of a proceeding in equity and record the evidence thereof, as provided in this chapter; provided, however, that this act shall not apply to titles acquired by a municipality under certificates of tax sales purchased and held by it at tax sales conducted therein which titles so acquired and certificates of tax sales are hereby expressly exempted from said limitation period of 20 years. The limitation period of 20 years of this section shall not apply to a title and the certificate of tax sale acquired by a purchaser, his heirs or assigns when that purchaser, his heirs or assigns establish that all property taxes have been paid by him, his heirs or assigns in each year since the purchase of the certificate.
N.J.S. § 54:5-79