In a large pot bring 6 cups water to boiling. Add crab legs; cover and steam 5 to 7 minutes. Remove from heat and place crab legs on a serving platter.
Meanwhile, place butter in a medium saucepan over medium-low heat; cook 5 minutes or until butter is completely melted. Skim solids off the top; discard solids. Slowly pour butter into a heat-proof serving dish (discard solids left in pan). Stir in lemon juice, parsley and basil, keep warm until ready to serve.
Serve crab legs with warm butter sauce for dipping.