▁office ▁issued ▁United ▁States ▁pat ents ▁to ▁the ▁Feld mans ▁number ed ▁ 5 , 5 5 3 , 9 5 9 ▁( 1 9 9 6 ) ▁and ▁ 5 , 7 4 9 , 6 6 7 ▁( 1 9 9 8 ). ▁For ▁a ▁time , ▁Le ven ger ▁Company ▁bought ▁not ebook s ▁and ▁supplies ▁for ▁the ▁disk - binding ▁system ▁from ▁Roll ab ind , ▁Inc ▁which ▁at ▁the ▁time ▁was ▁controlled ▁by ▁Mitch ▁Green berg ▁and ▁Ed ▁F inkel stein ▁with ▁Feld man ▁being ▁a ▁ 1 / 3 ▁partner . ▁Le ven ger ▁sold ▁the ▁not ebook s ▁and ▁supplies ▁under ▁its ▁own ▁Cir ca ▁brand ▁name . ▁In ▁ 2 0 0 2 , ▁Green berg ▁and ▁F inkel stein ▁sold ▁their ▁interest ▁in ▁the ▁company ▁to ▁a ▁group ▁led ▁by ▁Michael ▁Ol sh er ▁with ▁Feld man ▁still ▁involved ▁and ▁formed ▁a ▁new ▁company , ▁Roll ab ind , ▁L LC . ▁After ▁about ▁ 2 ▁years , ▁the ▁Ol sh er ▁group ▁sold ▁out ▁to ▁another ▁individual ▁who ▁inv ested ▁an ▁und is closed ▁sum ▁but ▁was ▁out ▁in ▁just ▁over ▁ 1 ▁year ▁after ▁losing ▁their ▁invest ment . ▁In ▁ 2 0 0 4 , ▁the ▁Feld mans ▁lic ensed ▁Le ven ger ▁under ▁their ▁pat ents ▁to ▁manufact ure ▁the ▁not ebook s ▁and ▁supplies . ▁In ▁early ▁ 2 0 0 6 , ▁Le ven ger ▁learned ▁that ▁St ap les ▁and ▁Target ▁market ed ▁not ebook s ▁similar