Insiders know a lot about the companies they work for, so watching their actions can help bank some serious profits. These transactions can be monitored by the public through forms 3, 4, and 5 filed with the U.S. Securities and Exchange Commission (SEC). Here are the top 5 insider buys from last week, which can be useful when creating a watchlist of stocks with a potential catalyst for this week:

1. Lamar Advertising Company (LAMR) - 10% owner Edward McDermott purchase a substantial block of shares valued at over $20 million.
2. Stericycle Inc. (SRCL) - The company's chairman and director each purchased substantial blocks of shares valued at over $10 million.
3. Orbitz Worldwide, Inc. (OWW) - Par Capital Management Inc. purchased over $12 million in new shares.
4. Saks Inc. (SKS) - Inmobiliaria Carso purchased over a million shares for nearly $10 million.
5. Hearst Argyle Television Inc. (HTV) - Hearst Family Trust purchased nearly a half million shares in a transaction worth some nearly $10 million.