Seoi nage is a shoulder throw, one of the traditional forty throws of Judo as developed by Jigoro Kano. It belongs to the first group, Dai Ikkyo, of the traditional throwing list, Gokyo (no waza), of Kodokan Judo. It is also part of the current 67 Throws of Kodokan Judo. It is classified as a hand technique, Te-Waza.
The specific techniques of morote-seoi-nage (two hands seoi-nage) or eri-seoi are generally called seoi-nage. The distinctive technical aspect of this classification is that tori (the one executing the technique) grips with his two hands as opposed to Ippon Seoi Nage in which only one hand remains gripping while the other slides under uke’s (the one receiving the technique) armpit. Seoi nage is one of the highest-scoring techniques in Judo. Renown seoinage martial artists are Isao Okano and Toshihiko Koga. In BJJ, famous seoinage competitors include Saulo Ribeiro, Fernando Margarida, Ronaldo Jacare, and Rodolfo Vieira.
In this video, Kurt Osiander shows a modified Drop Seoi Nage that works well for BJJ, using a double sleeve control:
This video from Matt D’Aquino shows 10 setups you can use for your ippon seoi nage. By having mulitpe options with your seoi you have a way better chance of hitting it during randori or shiai.
Matt D’Aquino is a multiple Australian and Oceania Champion and a 2008 Beijing Judo Olympian. He has been studying Judo for over 23 years. He is a 3rd Degree Black belt and a purple belt in BJJ. Matt is also known worldwide for his excellent website Beyondgrappling.com . Matt has also come out with a great new DVD set for BJJ players: Judo for BJJ.