If Julius Ceasar had heeded the soothsayer, you wouldn't be reading this story because the Ides of March would have passed into forgotten Roman history. Alas, Ceasar did not listen to the warning. He was stabbed by Roman senators in 44BCE on March 15th.

William Shakespeare brought us the line "Beware the Ides of March!" in his play, Julius Ceasar. But the Romans had long held the ides (the middle of every month, either the 13th or the 15th) as sacred to the god Jupiter and kept them as legal public holidays. Courts closed, public business ceased, employees and even slaves refrained from work.

The Ides of March were also sacred to Mars, the God of War, for whom March was named. Military parades and assemblies were often held to commemorate this god and display the might of the Roman army. March was the first month of the year for Romans, who marked it with new year celebrations.

The Ides of March this year should be heeded by all patent filers. It's is the last day on which a patent application can be filed in the U.S. without the risk of being examined under new, more stringent rules.

In Canada, the day is celebrated with the drinking of Bloody Caesar cocktails.