Erm, yes it does - but keep thinking.
http://www.google.co.uk/search?gcx=w&sourceid=chrome&ie=UTF-8&q=encumbered+patent#sclient=psy-ab&hl=en&source=hp&q=%22frand+encumbered%22&pbx=1&oq=%22frand+encumbered%22&aq=f&aqi=&aql=1&gs_sm=e&gs_upl=14990l25855l0l26271l30l16l5l7l8l1l255l2303l4.10.2l26l0&bav=on.2,or.r_gc.r_pw.,cf.osb&fp=e77a90f121cf88b&biw=796&bih=582