Whisk together flour, baking soda, salt and cinnamon in a small bowl; set aside.
Cream butter, shortening and sugar until fluffy and smooth. Beat in eggs one a time. Stir in corn syrup and vanilla.
Gradually add flour mixture until just combined, then gently stir in the oats and raisins. Cover and refrigerate dough 20-30 minutes.
Preheat oven to 350 degrees.
Scoop dough in tablespoons using a cookie scoop to ensure they're all the same size and drop onto parchment paper-lined cookie sheets about two inches apart. Cookies will spread just a little. Bake 12 minutes or until just set and a light golden brown. Cool 5 minutes on cookie sheet before transferring to a wire rack to cool completely. Store in airtight container.