On Thursday, September 12, the California Board of Equalization (BOE) issued a Memorandum Opinion stating that Barnesandnoble.com was obligated to pay California back use taxes for a period of four-plus months -- from November 15, 1999, to March 31, 2000. BOE ruled that, because the bricks-and-mortar Barnes & Noble stores were offering customers coupons that discounted purchases made at its online store, Barnesandnoble.com had established a physical presence, or nexus, in the state of California.