Something off about insider activity on OpenInsider

I sometimes run into an insider that sees a decrease in the number of stocks owned without a corresponding “sale” event. How does that make sense?

One example of this is the CEO of NASDAQ:SQFT, Heilbron Jack Kendrick. OpenInsider doesn't show a single sale event yet the amount of stock he owns keeps getting reset over the years.

http://openinsider.com/screener?s=&o=1437208&pl=&ph=&ll=&lh=&fd=730&fdr=&td=0&tdr=&fdlyl=&fdlyh=&daysago=&xp=1&xs=1&xa=1&xd=1&vl=&vh=&ocl=&och=&sic1=-1&sicl=100&sich=9999&grp=0&nfl=&nfh=&nil=&nih=&nol=&noh=&v2l=&v2h=&oc2l=&oc2h=&sortcol=0&cnt=100&page=1