N.Y.C. Admin. Code § 7-619: § 7-619 Destroying obsolete documents and records.

The register is authorized to destroy any or all chattel mortgages, chattel mortgage indices, certificates of stockholders' consent to the execution of mortgages of chattels, bills of sale, conditional bills of sale affecting real property or other filed instruments affecting chattels, on file in the register's office after the expiration of five years from the date of filing, and any daily index or tickler more than two years old and which has been replaced by permanent block and alphabetical indices as provided for in this chapter, and all surplus copies of land maps of any of the counties of the city more than ten years old, which have not been disposed of by sale or otherwise.