$OPXS Here's what I could find on opxs shares:
Accredited Investor's Share's are Shorted
US LONGS HAVE THAT SHORTED SHARE TOTALs
HOLD STRONG LONGS

2009 Private Placement Stock Holders $1,300,800
8,130,000 they gave .16 and couldn't sell

Their .45 Warrant's 8,130,000
They bought in - 5,401,667 Share's
Share's reduced .01 and couldn't sell

2,730,000 left to exercise by March 29 2014 at .45
(My guess is these Warrants will be exercised before March 29 2014)

Accredited Investor's paid $1,354,816.67 average .10
for - 13,531,667 share's and couldn't sell

These are where the shorted share's come from

Some has sold but for a loss, those that waited, are the shorted share's