As of today's market close, here are the top 10 names showing unusual option activity on tradeMONSTER's LiveAction data system.
Exeter Resource (XRA): Option volume 3,069 percent above average. Investors bought February 5 calls and sold the August 5 calls against open interest, suggesting a short calendar spread was closed. XRA rose 3.79 percent to $4.66.
Mobile Telesystems (MBT): Option volume 1,717 percent above average. Investors bought the September 18 puts and the December 18 calls. MBT fell 0.66 percent to $16.65.
Teradyne ETF (TER): Option volume 1,472 percent above average. About 10,000 January 10 puts were purchased for $1.55 but volume was below open interest. TER fell 4.81 percent to $11.87.
Investment Technology Group (ITG): Option volume 1,426 percent above average. A block of 2,000 August 12.50 puts was bought for $1.15 to $1.25. ITG fell 4.63 percent to $11.33.
E-House China Holdings iShares Malaysia ETF (EJ): Option volume 1,180 percent above average. About 1,600 August 6 puts were bought for $0.10 to $0.20. EJ fell 6.20 percent to $6.66.
Rounding out the rest of the top 10 are:
- Arrow Electronics (ARW): Option volume 1,160 percent above average.
- VanceInfo Technologies (VIT): Option volume 961 percent above average.
- CBOE Mini Index (MNX): Option volume 951 percent above average.
- Raptor Pharmaceutical (RPTP): Option volume 865 percent above average.
- Kinetic Concepts (KCI): Option volume 692 percent above average.

(Chart courtesy of tradeMONSTER)
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The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.