The DADE linker is a pre-activated carboxyl linker for the 5’ terminus of an oligonucleotide. It was designed for the solid phase conjugation of amine bearing compounds directly to an oligonucleotide, although it has other applications. If it is left in its activated form when the oligonucleotide is deprotected, it will react with the prevalent nucleophile in the solution (ammonia in ammonium hydroxide forming the amide, the hydroxyl in sodium hydroxide forming carboxylic acid, etc.). Its major advantage is that it can be used for solid phase conjugation to amine bearing compounds, negating the need for costly succinimidyl esters. This allows high throughput screening, and the reuse of compound that did not conjugate in the first reaction. It also allows for the use of large excesses that will enhance conjugation efficiencies, and reduce cost. It has many other applications.