By Jud Pyle, CFA, chief investment strategist for the Options News NetworkLooking at the July 45 calls in Fluor ( FLR), we find that they have traded more than 5,000 times so far today vs. current open interest of 2,455. We also find that the July 55 calls have traded more than 5,000 times vs. an open interest of 1,033. What is interesting about this call activity is that it was a bullish call spread and it gives one picture into a way to take advantage of potential upside in FLR. FLR reached a 52-week low on Nov. 21 of $28.60. Now today, with the stock having rallied back up to around $37.90, an investor purchased the July 45-55 call spread for around $2.25. That means that the investor bought the 45 calls and sold the 55 calls. If FLR is above 55 at July expiration, the investor will attain the max profit of $7.75.